Remove Hack used in blink side for merging dependent chromium and blink patches.

To merge the dependent patches https://codereview.chromium.org/137893025/ and https://codereview.chromium.org/138523003/ ,
older definition of the function didActivateCompositor() was also needed to be kept at both chromium and blink side.
This was introduced in https://codereview.chromium.org/189263019/ . Since all of the patches have landed now, we can land this final patch which removes the older definitions from the blink side.

BUG=None
TBR=jamesr@chromium.org

Review URL: https://codereview.chromium.org/248313003

git-svn-id: svn://svn.chromium.org/blink/trunk@172415 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Add <label> to items in Event Listener Breakpoint of Chrome Dev Tools

At present, when attempting to set an event listener breakpoint
within the Event Listener Breakpoint section of the Sources
tab of Chrome Dev Tools, you must click on the checkbox.

This CL adds a <label> so a user can simply click on the associated
text and the checkbox will be clicked.

BUG=360404

Review URL: https://codereview.chromium.org/244573002

git-svn-id: svn://svn.chromium.org/blink/trunk@172416 bbb929c8-8fbe-4397-9dbb-9b2b20218538