FCMify layout tests that check for no layer trees

These all just add layer trees in the text output where previously there
was not layer trees.  It's easier to just change this subset to force
compositing mode now so that they'll continue to work when all tests
become force compositing later.

BUG=361729

Review URL: https://codereview.chromium.org/247033003

git-svn-id: svn://svn.chromium.org/blink/trunk@172325 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Skip XMLHttpRequest.send performance test

It crashes the Android Nexus4 bot, thus causing noise for perf sheriffs.

BUG=353299
TBR=tonyg@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/248533003

git-svn-id: svn://svn.chromium.org/blink/trunk@172326 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Update LeakExpectations to include known leaks and remove fixed leaks

+ marked more SharedWorkers tests as leaking
+ marked more selection tests as leaking
+ marked more drag tests as leaking
- filesystem directory callbacks are no longer leaking
- http/tests/misc/acid3.html is no longer leaking
- Tests using leak-check.js are now working

NOTRY=true
BUG=364377, 364390, 364391, 364392, 364394, 364395, 364407, 364408, 365180, 365182

Review URL: https://codereview.chromium.org/248573002

git-svn-id: svn://svn.chromium.org/blink/trunk@172327 bbb929c8-8fbe-4397-9dbb-9b2b20218538