Add Matched Style Parameter to UI Devtools getMatchedStylesForNode

Updated protocol and CSSAgent to send matched style to the front end
from UI Devtools. This will allow for the feature of grouping
properties in the elements pane.

Bug: 973698
Change-Id: I3895a6c0b5beaf3c988e20afcf3cf90d50541560
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1657352
Reviewed-by: Wei Li <weili@chromium.org>
Commit-Queue: Kristyn Hamasaki <khamasaki@google.com>
Cr-Commit-Position: refs/heads/master@{#670110}
1 file changed