Android: Improve back button handling when the keyboard is visible #36

Job	Run time
build-emscripten	41s
build-android (armeabi-v7a)	29s
build-appletvos (objc_arc)	47s
build-android (armeabi-v7a with NEON)	32s
build-appletvos (no_objc_arc)	31s
build-android (arm64-v8a)	40s
build-appletvsimulator (objc_arc)	38s
build-android (x86)	32s
build-appletvsimulator (no_objc_arc)	49s
build-android (x86_64)	30s
build-iphoneos (objc_arc)	56s
build-iphoneos (no_objc_arc)	48s
build-iphonesimulator (objc_arc)	34s
build-iphonesimulator (no_objc_arc)	57s
build-macosx (objc_arc)	32s
build-macosx (no_objc_arc)	46s
	10m 42s

Provide feedback