[FastTextAutosizer] Enable the non-flaky hackernews-comments.html test

hackernews-comments.html was marked as flaky in crbug.com/343201 but
no longer appears to be flaky. This is likely from our recent
improvements in this area.

BUG=343201
TBR=skobes
NOTRY=true

Review URL: https://codereview.chromium.org/238983004

git-svn-id: svn://svn.chromium.org/blink/trunk@171674 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Use Traits in V8StringResource to avoid code duplication

Use Traits in V8StringResource to avoid code duplication in
StringTraits::fromV8String() for 1-byte / 2-bytes v8::String.

This also gets rid of template specializations for the oneByte boolean
argument which makes the code a bit clearer as fromV8String<false> /
fromV8String<true> was not very readable.

There is no visible impact on performance according to Dromaeo DOM Core:
http://dromaeo.com/?id=219949,219955

The binary size is slightly smaller (184 bytes), likely because the compiler is
able to simplify the code further as fromV8String() is now implicitly inlined
but it wasn't before due to template specialization.

R=haraken@chromium.org, adamk@chromium.org

Review URL: https://codereview.chromium.org/238533002

git-svn-id: svn://svn.chromium.org/blink/trunk@171677 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Limit the number of output channels for a ChannelMergerNode.

Add a new test for this.

See the discussion in https://github.com/WebAudio/web-audio-api/issues/312. There appears to be general agreement that the number of outputs should be limited to 32 (or the implementation maximum) and any extras are ignored.

BUG=345174

Review URL: https://codereview.chromium.org/226663005

git-svn-id: svn://svn.chromium.org/blink/trunk@171678 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: fix console getting broken if reloaded with active filter

This patch moves target observing to the end of ConsoleView constructor
so that all the objects are created prior the targetAdded callbacks.

Review URL: https://codereview.chromium.org/237533006

git-svn-id: svn://svn.chromium.org/blink/trunk@171679 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Adds accessibility attributes for "embed", "object" and "applet" tags.

R=dmazzoni,dtseng
BUG=348259

Review URL: https://codereview.chromium.org/231883009

git-svn-id: svn://svn.chromium.org/blink/trunk@171680 bbb929c8-8fbe-4397-9dbb-9b2b20218538