Revert of DevTools: don't change current selection on Timeline flame chart when overview window changes (patchset #1 id:1 of https://codereview.chromium.org/695903002/)

Reason for revert:
There is a blocking issue of shift+drag being non discoverable that needs to be addressed first.

Original issue's description:
> DevTools: don't change current selection on Timeline flame chart when overview window changes
> 
> Shift+drag is more convenient for specifying the range of interest it's better to avoid also binding the selection to the current range in the overview pane.
> 
> Waterfall view will still populate its details view with the data for selected range in the overview pane.
> 
> BUG=426152
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=184904

TBR=loislo@chromium.org,caseq@chromium.org,yurys@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=426152

Review URL: https://codereview.chromium.org/704233002

git-svn-id: svn://svn.chromium.org/blink/trunk@184914 bbb929c8-8fbe-4397-9dbb-9b2b20218538