Pepper: Fix channel init in ProxyChannel.

Previously, there was no way to savely add filters to the underlying
SyncChannel in a ProxyChannel safely.

This change splits channel initialization into two methods so there's a clear
step where filters may be added safely.

BUG=343768

Review URL: https://codereview.chromium.org/179743005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@253408 0039d316-1c4b-4281-b951-d872f2087c98
Split Convolver.SIMDVerification into two tests

Split Convolver.SIMDVerification into two tests, one which tests all tricky edge cases and one
that tests that large scales don't end up distorting the results when using SIMD. Also enable
running these tests with DEBUG and TSAN.

On my machine, running with DEBUG and ASAN, this test went from 60 seconds to 10 seconds.
Hope that is fast enough, as the additional coverage would be nice to have.

BUG=134400

Review URL: https://codereview.chromium.org/178013006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@253409 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 253409
De-flakify MetricsServiceTest.RegisterSyntheticTrial.

The test relied on TimeTicks::Now() changing between
several lines of code. This is flaky, since on a
sufficiently fast machine, that may not end up the
case.

This CL fixes that cause of flakyness (and re-enables
the test) by making sure TimeTicks::Now() changes.
According to the docs for TimeTicks::Now(), its
resolution is ~1-15ms, so this shouldn't cause a
huge delay in the test.

Also changes the SyntheticTrialGroup constructor
to not take the start_time parameter since it gets
clobbered by the API anyway.

BUG=320433

Review URL: https://codereview.chromium.org/178383002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@253410 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 253410
Cleanup: Remove some cruft and add more asserts in NativeMessagingTest.

Review URL: https://codereview.chromium.org/178643003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@253411 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 253411