Cross-origin fragment navigations should happen asynchronously.

We currently special-case fragment-only navigation (e.g. "page.html" to
"page.html#anchor") in NavigationScheduler::scheduleLocationChange to
bypass the scheduling bit, and synchronously perform the navigation. This
patch skips that optimization for navigations that originate cross-origin.

If a document on "a.com" frames a document on "b.com", synchronous navigation
of that frame is problematic for two reasons:

1. Synchronous anything is bad for cross-process communication: this
   optimization would make it difficult for us to split processes along origin
   boundries while maintaining performance.

2. Timing attacks on the navigation along the lines of [1] are much more
   reliable if the navigation synchronously resolves. We increase the flakyness
   of such attacks by moving to an async model.

[1]: http://homakov.blogspot.de/2013/03/pwning-your-privacy-in-all-browsers.html

BUG=178632

Review URL: https://chromiumcodereview.appspot.com/14622021

git-svn-id: svn://svn.chromium.org/blink/trunk@153992 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove 8BIT_TEXTRUN flag.

It is now enabled by default.

Review URL: https://chromiumcodereview.appspot.com/17273003

git-svn-id: svn://svn.chromium.org/blink/trunk@153993 bbb929c8-8fbe-4397-9dbb-9b2b20218538