Revert 181427 "Reduce hit test on ShowPress by moving hit testin..."

> Reduce hit test on ShowPress by moving hit testing to WebViewImpl.
> 
> Previously there was a hit test for link highlighting in WebViewImpl and then a                                          
> separate one in EventHandler::handleGestureEvent. This CL makes it so that a                                             
> single hit test in WebViewImpl is reused by the EventHandler. Scroll events                                              
> still need to hit test in a separate fashion though and their handling has been                                          
> refactored into a separate code path.
> 
> BUG=381728
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=181009
> 
> Review URL: https://codereview.chromium.org/490783003

TBR=zeeshanq@chromium.org

Review URL: https://codereview.chromium.org/546693002

git-svn-id: svn://svn.chromium.org/blink/trunk@181434 bbb929c8-8fbe-4397-9dbb-9b2b20218538