title: Gradle mixing versions 27.1.1 and 26.1.0
body: <p>I'm getting an error in my app-level build.gradle where on the first support library I am using, it tells me that all com.android.support libraries must use the exact same version specification and that it's found versions 27.1.1 and 26.0.2.  In my app-level build.gradle, there is no line using 26.1.0.  Also, all <code>compile</code> statements have been changed to <code>implementation</code>, the <code>compileSdkVersion</code> is 27 and the <code>targetSdkVersion</code> is 27.  To attempt to find the culprit, I ran:</p>
  
  <pre><code>./gradlew -q dependencies app:dependencies --configuration debugAndroidTestCompileClasspath
  </code></pre>
  
  <p>And got the following output:</p>
  
  <pre><code>registerResGeneratingTask is deprecated, use registerGeneratedResFolders(FileCollection)
  registerResGeneratingTask is deprecated, use registerGeneratedResFolders(FileCollection)
  
  ------------------------------------------------------------
  Root project
  ------------------------------------------------------------
  
  No configurations
  
  ------------------------------------------------------------
  Project :app
  ------------------------------------------------------------
  
  debugAndroidTestCompileClasspath - Resolved configuration for compilation for variant: debugAndroidTest
  +--- com.android.support.test:runner:1.0.1
  |    +--- com.android.support:support-annotations:25.4.0 -&gt; 27.1.1
  |    +--- junit:junit:4.12
  |    |    \--- org.hamcrest:hamcrest-core:1.3
  |    \--- net.sf.kxml:kxml2:2.3.0
  +--- com.android.support.test.espresso:espresso-core:3.0.1
  |    +--- com.android.support.test:runner:1.0.1 (*)
  |    +--- com.android.support.test:rules:1.0.1
  |    |    \--- com.android.support.test:runner:1.0.1 (*)
  |    +--- com.android.support.test.espresso:espresso-idling-resource:3.0.1
  |    +--- com.squareup:javawriter:2.1.1
  |    +--- javax.inject:javax.inject:1
  |    +--- org.hamcrest:hamcrest-library:1.3
  |    |    \--- org.hamcrest:hamcrest-core:1.3
  |    +--- org.hamcrest:hamcrest-integration:1.3
  |    |    \--- org.hamcrest:hamcrest-library:1.3 (*)
  |    \--- com.google.code.findbugs:jsr305:2.0.1
  +--- com.android.support:appcompat-v7:27.1.1
  |    +--- com.android.support:support-annotations:27.1.1
  |    +--- com.android.support:support-core-utils:27.1.1
  |    |    +--- com.android.support:support-annotations:27.1.1
  |    |    \--- com.android.support:support-compat:27.1.1
  |    |         +--- com.android.support:support-annotations:27.1.1
  |    |         \--- android.arch.lifecycle:runtime:1.1.0
  |    |              +--- android.arch.lifecycle:common:1.1.0
  |    |              \--- android.arch.core:common:1.1.0
  |    +--- com.android.support:support-fragment:27.1.1
  |    |    +--- com.android.support:support-compat:27.1.1 (*)
  |    |    +--- com.android.support:support-core-ui:27.1.1
  |    |    |    +--- com.android.support:support-annotations:27.1.1
  |    |    |    +--- com.android.support:support-compat:27.1.1 (*)
  |    |    |    \--- com.android.support:support-core-utils:27.1.1 (*)
  |    |    +--- com.android.support:support-core-utils:27.1.1 (*)
  |    |    +--- com.android.support:support-annotations:27.1.1
  |    |    +--- android.arch.lifecycle:livedata-core:1.1.0
  |    |    |    +--- android.arch.lifecycle:common:1.1.0
  |    |    |    +--- android.arch.core:common:1.1.0
  |    |    |    \--- android.arch.core:runtime:1.1.0
  |    |    |         \--- android.arch.core:common:1.1.0
  |    |    \--- android.arch.lifecycle:viewmodel:1.1.0
  |    +--- com.android.support:support-vector-drawable:27.1.1
  |    |    +--- com.android.support:support-annotations:27.1.1
  |    |    \--- com.android.support:support-compat:27.1.1 (*)
  |    \--- com.android.support:animated-vector-drawable:27.1.1
  |         +--- com.android.support:support-vector-drawable:27.1.1 (*)
  |         \--- com.android.support:support-core-ui:27.1.1 (*)
  +--- com.android.support:design:27.1.1
  |    +--- com.android.support:support-v4:27.1.1
  |    |    +--- com.android.support:support-compat:27.1.1 (*)
  |    |    +--- com.android.support:support-media-compat:27.1.1
  |    |    |    +--- com.android.support:support-annotations:27.1.1
  |    |    |    \--- com.android.support:support-compat:27.1.1 (*)
  |    |    +--- com.android.support:support-core-utils:27.1.1 (*)
  |    |    +--- com.android.support:support-core-ui:27.1.1 (*)
  |    |    \--- com.android.support:support-fragment:27.1.1 (*)
  |    +--- com.android.support:appcompat-v7:27.1.1 (*)
  |    +--- com.android.support:recyclerview-v7:27.1.1
  |    |    +--- com.android.support:support-annotations:27.1.1
  |    |    +--- com.android.support:support-compat:27.1.1 (*)
  |    |    \--- com.android.support:support-core-ui:27.1.1 (*)
  |    \--- com.android.support:transition:27.1.1
  |         +--- com.android.support:support-annotations:27.1.1
  |         \--- com.android.support:support-compat:27.1.1 (*)
  +--- com.android.support.constraint:constraint-layout:1.1.0
  |    \--- com.android.support.constraint:constraint-layout-solver:1.1.0
  +--- com.android.support:support-vector-drawable:27.1.1 (*)
  +--- com.android.support:support-v4:27.1.1 (*)
  +--- com.android.support:cardview-v7:27.1.1
  |    \--- com.android.support:support-annotations:27.1.1
  +--- com.android.support:recyclerview-v7:27.1.1 (*)
  +--- com.google.android.gms:play-services-ads:15.0.0
  |    +--- com.android.support:customtabs:26.1.0
  |    |    +--- com.android.support:support-compat:26.1.0 -&gt; 27.1.1 (*)
  |    |    \--- com.android.support:support-annotations:26.1.0 -&gt; 27.1.1
  |    +--- com.google.android.gms:play-services-ads-base:[15.0.0] -&gt; 15.0.0
  |    +--- com.google.android.gms:play-services-ads-identifier:[15.0.0,16.0.0) -&gt; 15.0.0
  |    |    \--- com.google.android.gms:play-services-basement:[15.0.0,16.0.0) -&gt; 15.0.0
  |    |         \--- com.android.support:support-v4:26.1.0 -&gt; 27.1.1 (*)
  |    +--- com.google.android.gms:play-services-ads-lite:[15.0.0] -&gt; 15.0.0
  |    |    +--- com.google.android.gms:play-services-ads-base:[15.0.0] -&gt; 15.0.0
  |    |    \--- com.google.android.gms:play-services-basement:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |    +--- com.google.android.gms:play-services-basement:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |    \--- com.google.android.gms:play-services-gass:[15.0.0] -&gt; 15.0.0
  |         +--- com.google.android.gms:play-services-ads-base:[15.0.0] -&gt; 15.0.0
  |         \--- com.google.android.gms:play-services-basement:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  +--- com.google.firebase:firebase-core:15.0.0
  |    \--- com.google.firebase:firebase-analytics:[15.0.0,16.0.0) -&gt; 15.0.0
  |         +--- com.google.android.gms:play-services-basement:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |         +--- com.google.android.gms:play-services-measurement-base:[15.0.0] -&gt; 15.0.0
  |         +--- com.google.android.gms:play-services-stats:[15.0.0,16.0.0) -&gt; 15.0.0
  |         |    \--- com.google.android.gms:play-services-basement:[15.0.0] -&gt; 15.0.0 (*)
  |         +--- com.google.firebase:firebase-analytics-impl:[15.0.0] -&gt; 15.0.0
  |         |    +--- com.google.android.gms:play-services-ads-identifier:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |         |    +--- com.google.android.gms:play-services-basement:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |         |    +--- com.google.android.gms:play-services-measurement-base:[15.0.0] -&gt; 15.0.0
  |         |    +--- com.google.android.gms:play-services-stats:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |         |    +--- com.google.android.gms:play-services-tasks:[15.0.0,16.0.0) -&gt; 15.0.0
  |         |    |    \--- com.google.android.gms:play-services-basement:[15.0.0] -&gt; 15.0.0 (*)
  |         |    +--- com.google.firebase:firebase-common:[15.0.0,16.0.0) -&gt; 15.0.0
  |         |    |    +--- com.google.android.gms:play-services-basement:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |         |    |    \--- com.google.android.gms:play-services-tasks:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |         |    \--- com.google.firebase:firebase-iid:[15.0.0] -&gt; 15.0.0
  |         |         +--- com.google.android.gms:play-services-basement:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |         |         +--- com.google.android.gms:play-services-measurement-base:[15.0.0] -&gt; 15.0.0
  |         |         +--- com.google.android.gms:play-services-stats:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |         |         +--- com.google.android.gms:play-services-tasks:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |         |         \--- com.google.firebase:firebase-common:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |         \--- com.google.firebase:firebase-common:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  +--- com.google.firebase:firebase-database:15.0.0
  |    +--- com.google.android.gms:play-services-basement:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |    +--- com.google.android.gms:play-services-tasks:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |    +--- com.google.firebase:firebase-common:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |    +--- com.google.firebase:firebase-database-collection:[15.0.0,16.0.0) -&gt; 15.0.0
  |    |    \--- com.google.android.gms:play-services-basement:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |    \--- com.google.firebase:firebase-database-connection:[15.0.0] -&gt; 15.0.0
  |         +--- com.google.android.gms:play-services-basement:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |         +--- com.google.firebase:firebase-analytics:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |         \--- com.google.firebase:firebase-common:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  +--- com.google.firebase:firebase-firestore:15.0.0
  |    +--- com.google.android.gms:play-services-basement:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |    +--- com.google.android.gms:play-services-tasks:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |    +--- com.google.firebase:firebase-analytics:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |    +--- com.google.firebase:firebase-common:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |    +--- com.google.firebase:firebase-database-collection:[15.0.0,16.0.0) -&gt; 15.0.0 (*)
  |    \--- com.squareup.okhttp:okhttp:2.7.2
  |         \--- com.squareup.okio:okio:1.6.0
  +--- com.aurelhubert:ahbottomnavigation:2.1.0
  |    \--- com.android.support:design:25.3.1 -&gt; 27.1.1 (*)
  +--- com.github.bumptech.glide:glide:4.5.0
  |    +--- com.github.bumptech.glide:gifdecoder:4.5.0
  |    |    \--- com.android.support:support-annotations:27.0.2 -&gt; 27.1.1
  |    +--- com.github.bumptech.glide:disklrucache:4.5.0
  |    +--- com.github.bumptech.glide:annotations:4.5.0
  |    \--- com.android.support:support-fragment:27.0.2 -&gt; 27.1.1 (*)
  +--- de.hdodenhof:circleimageview:2.2.0
  +--- me.tankery.lib:circularSeekBar:1.1.4
  +--- com.github.fiskurgit:ChipCloud:3.0.5
  |    \--- com.android.support:appcompat-v7:25.1.1 -&gt; 27.1.1 (*)
  \--- com.google.android:flexbox:0.3.2
  
  (*) - dependencies omitted (listed previously)
  </code></pre>
  
  <p>Here it shows that <code>com.android.support:customtabs:26.1.0</code> in <code>com.google.android.gms:play-services-ads:15.0.0</code> is using 26.1.0 but in the drilldown it has <code>-&gt; 27.1.1 (*)</code> which I'm assuming means that it's using 27.1.1 instead?  I'm getting the same thing from <code>com.android.support:support-v4:26.1.0</code> in play-services.  What could be causing this error?</p>