Simplify setting lockBackForwardList() in NavigationScheduler.

Simplify setting lockBackForwardList() in NavigationScheduler.

Remove ScheduledNavigation::didStartTimer() and
HistoryController::currentItemShouldBeReplaced(). Replace
then with a new state on FrameLoaderStateMachine and inline
the new check in
NavigationScheduler::mustLockBackForwardList().

BUG=321280
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=162384

[Nate Chapin, 2013-11-19 20:05:25]

https://codereview.chromium.org/76653002/diff/1/Source/core/loader/FrameLoade...
File Source/core/loader/FrameLoader.cpp (left):

https://codereview.chromium.org/76653002/diff/1/Source/core/loader/FrameLoade...
Source/core/loader/FrameLoader.cpp:1302: // proxy for
history()->currentItemShouldBeReplaced().
This sentence wasn't accurate, and now it's obsolete, too.

[abarth-chromium, 2013-11-20 05:22:03]

lgtm

https://codereview.chromium.org/76653002/diff/1/Source/core/loader/Navigation...
File Source/core/loader/NavigationScheduler.cpp (right):

https://codereview.chromium.org/76653002/diff/1/Source/core/loader/Navigation...
Source/core/loader/NavigationScheduler.cpp:288: return true;
Wow, much nicer.

[commit-bot: I haz the power, 2013-11-20 17:41:33]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/japhet@chromium.org/76653002/1

[commit-bot: I haz the power, 2013-11-20 18:20:27]

Change committed as 162384