View source uses too many resources and never finishes on some pages.

Analysis: it takes very long to update CSS counters used for line numbers.

BUG=265747

Review URL: https://chromiumcodereview.appspot.com/20646007

git-svn-id: svn://svn.chromium.org/blink/trunk@155438 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Auto-rebaseline for r155428

http://src.chromium.org/viewvc/blink?view=revision&revision=155428

TBR=morrita@chromium.org

Review URL: https://codereview.chromium.org/21915003

git-svn-id: svn://svn.chromium.org/blink/trunk@155439 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: [Elements] Restore the original attribute value before editing

If a property value is trimmed, then it should be restored to the
original value before editing.

R=vsevik, yurys@chromium.org
BUG=263752

Review URL: https://chromiumcodereview.appspot.com/20712003

git-svn-id: svn://svn.chromium.org/blink/trunk@155440 bbb929c8-8fbe-4397-9dbb-9b2b20218538