SampleApp: Make android_install_app and android_launch_app work consistently

SampleApp: Make android_install_app and android_launch_app work consistently

Make android_install_app work more consistently:
* App can be "SampleApp" or "VisualBench"

Make android_launch_app work more consistently:
* Parameters to SampleApp are passed correctly
* SampleApp is actually launched

The parameters to "am" need to be quoted, since the command
is run on the device shell.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1589883002

Review URL: https://codereview.chromium.org/1589883002