Not showing "Consider using 'dppx' units instead of 'dpi',..." warning if dppx units are used.

Assume if the dppx unit is used in MediaQuerySet the author is aware of it and warning isn't needed.

Only one warning is generated per MediaQuerySet.

BUG=336276

Review URL: https://codereview.chromium.org/196473005

git-svn-id: svn://svn.chromium.org/blink/trunk@169249 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Oilpan: Remove all the RefPtrs and most of the raw pointers to style
sheets.

Comment on the cases where the raw pointers cannot be removed at this point.

Leave the raw pointers in inspector/ alove. They are safe as they are
now because the inspector leaks all the CSSStyleSheets it is inspecting
via Persistent handles at this point (and used to leak them all via
RefPtrs.)

R=erik.corry@gmail.com, haraken@chromium.org, oilpan-reviews@chromium.org, vegorov@chromium.org
BUG=

Review URL: https://codereview.chromium.org/199013003

git-svn-id: svn://svn.chromium.org/blink/trunk@169250 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove display() call from squashing LayoutTest

This test was calling display, as the animated gif would only invalidate
during paint calls.  This is a bit dodgy, as it relies on timing of the
gif and can't work unless an actual paint() occurs.

The test is trying to make sure that a non-CLM-owning layer inside of a
squashed layer only invalidates that layer and not more.  Therefore, a
change like updating the background color should be sufficient to verify
the same code.

BUG=345027

Review URL: https://codereview.chromium.org/199633002

git-svn-id: svn://svn.chromium.org/blink/trunk@169251 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: fix keyboard navigation in heap snapshot viewport

Review URL: https://codereview.chromium.org/195893020

git-svn-id: svn://svn.chromium.org/blink/trunk@169252 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Rename NO_TRACE_CHECKING to GC_PLUGIN_IGNORE.

R=ager@chromium.org
BUG=

Review URL: https://codereview.chromium.org/198113004

git-svn-id: svn://svn.chromium.org/blink/trunk@169253 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Use LocalStyleChange for classes in rightmost compound selector.

If we resort to not using invalidation sets, we can still use
LocalStyleChange instead of SubtreeStyleChange for classes in the rightmost
compound selector if the invalidation set approach was not dropped due to a
feature in the rightmost compound selector. For classes in other compound
selectors, still use SubtreeStyleChange.

Examples:

".a + .b" -> LocalStyleChange for "b", SubtreeStyleChange for "a"
".a .b::first-letter" -> SubtreeStyleChange for both "a" and "b".

R=esprehn@chromium.org,chrishtr@chromium.org
BUG=335247

Review URL: https://codereview.chromium.org/199373003

git-svn-id: svn://svn.chromium.org/blink/trunk@169255 bbb929c8-8fbe-4397-9dbb-9b2b20218538