22320 Move common graphics utils to //flutter/common/graphics (cla: yes, platform-android, platform-ios, waiting for tree to go green)

22321 Revert “Reland: Use dispatchKeyEventPreIme, and handle keys sent to InputConnection.sendKeyEvent on Android (#22304)” (cla: yes, platform-android)

22340 Use dispatchKeyEvent, and handle keys sent to InputConnection.sendKeyEvent on Android (cla: yes, platform-android)

22345 move deprecation from the PluginRegistry outer interface to inner, v1-specific fields (cla: yes, platform-android)

22353 PlatformViewIOS CreateExternalViewEmbedder refactor (cla: yes, platform-android, platform-ios)

22360 [android] Platform view creates external view embedder (cla: yes, platform-android, platform-ios, waiting for tree to go green)