Remove deprecated class WebContentsObserverAndroid and cleanup existing usages.
In continuation of the CL https://codereview.chromium.org/589113002/
this CL removes deprecated class WebContentsObserverAndroid and
cleans up existing usage of this class where ever it is occured.
This patch will be landed when external repositories has renamed
WebContentsObserverAndroid to WebContentsObserver
BUG=396118
Review URL: https://codereview.chromium.org/650333003
Cr-Commit-Position: refs/heads/master@{#300426}
2 files changed