75930 [flutter_tools] use less path manipulation in the Android SDK (cla: yes, tool)

75931 [flutter_tools] gradle cleanup 1 of 99999 (cla: yes, tool)

75933 Fix dart_docs. (cla: yes, team)

75937 [flutter_releases] Flutter Framework 1.26.0-17.6.pre Beta Cherrypicks (cla: yes, engine, f: material design, framework, tool)

75940 [flutter_tools] do not use context logger in gradle (cla: yes, tool, waiting for tree to go green)

75943 Reject unaccepted pointers in Drag recognizer (cla: yes, framework, waiting for tree to go green)