Update touch selection notification names, add ESTABLISHED.
Adds notification when a selection is established or dissolved,
and changes all the names of the notifications for selection
changes that are done when the handles are shown to include
_HANDLE_ or _HANDLES_.
This additional notification allows instrumentation tests in
ContextualSearchManagerTest to wait until the selection is
dissolved in the renderer to ensure correct touch handling.
Also add a unit test that demonstrates the selection-wait working.
BUG=487005
Review URL: https://codereview.chromium.org/1239583003
Cr-Commit-Position: refs/heads/master@{#339291}
7 files changed