21102 Handle malloc edge-case in mock_engine (cla: yes)

21107 Fix a AppLifecycleTest present time race between the animation and the rest of the test (cla: yes, platform-ios, waiting for tree to go green)

21109 Fix erroneous dartdoc @tool directive. (cla: yes, waiting for tree to go green)

21111 Update OCMock to version 3.7.1 (cla: yes)

21112 [web] Fix mis-aligned widget spans (cla: yes, platform-web)

21114 Fix comment indentation (cla: yes, platform-android)

21115 web: make a few variables non-null (cla: yes, platform-web)

21118 Check for a valid SkSL cache directory before calling VisitFiles (cla: yes)