Show label automatically for plug-ins of significant size
https://bugs.webkit.org/show_bug.cgi?id=106146
<rdar://problem/12783010>

Reviewed by Simon Fraser.

For significantly sized plug-ins, trigger a timer that displays the label automatically
without requiring the user to mouse over the element first. The trickiness of the logic
here is that there are two delays involved-- one for whether the user mouses over (shorter),
and one for when the label is shown automatically (longer). Mousing over a plug-in that is
marked to show it automatically should have the timer delay switched. And if the label
showed automatically, mousing in and out of the element should not change that label's
state.

* html/HTMLPlugInImageElement.cpp:
(WebCore): Add constants that determine whether the plug-in is of a significant size.
(WebCore::shouldPlugInShowLabelAutomatically): Based on the size of the frame view and the
clipped plug-in size, determine whether the label should show automatically. If the plug-in is
not contained within the bounds of the frame view, or is not at least as large as the threshold
size, then do not show the label automatically.
(WebCore::HTMLPlugInImageElement::subframeLoaderWillCreatePlugIn): After we've determined that
the plug-in should not auto-start, make a check to see if the label should show automatically.
Also, update some of the logging.
(WebCore::HTMLPlugInImageElement::subframeLoaderDidCreatePlugIn): Update the logging.

* platform/Timer.h:
(WebCore::DeferrableOneShotTimer::setDelay): Added to allow changing the delay of the timer. It
does not change any currently set timer, but should change the delay for the next one.

* rendering/RenderSnapshottedPlugIn.h: Rename the timer to m_showLabelDelayTimer since
it can fire for two different reasons. Add some additional state variables, and an enum
to explain why the label appeared.
* rendering/RenderSnapshottedPlugIn.cpp:
(WebCore): Change hoverDelay to showLabelAfterMouseOverDelay. Add a new, longer delay for
when the plug-in is supposed to auto-show the label.
(WebCore::RenderSnapshottedPlugIn::RenderSnapshottedPlugIn): Initialize the member variables.
(WebCore::RenderSnapshottedPlugIn::updateSnapshot): When the snapshot image is updated,
start the timer to auto-show the label.
(WebCore::RenderSnapshottedPlugIn::paintLabel): Avoid painting the label only if the element
is not hovered and the user was mousing over the plug-in. Otherwise, the plug-in is supposed
to show automatically, and we should paint. Mark the renderer as having showed the label at
least once.
(WebCore::RenderSnapshottedPlugIn::showLabelDelayTimerFired): Renamed to reflect the
purpose of the timer.
(WebCore::RenderSnapshottedPlugIn::setShouldShowLabelAutomatically): Set the variable that
determines whether, in general, this plug-in should show the label automatically even
without user input.
(WebCore::RenderSnapshottedPlugIn::handleEvent): If the user mouses over the plug-in,
only reset the show timer is the label has never appeared before, or if it has, that
it's not because the label was supposed to show automatically. That is, if the label is
supposed to show automatically, the label should remain visible. This is also true when
the user mouses out of the plug-in. If the user moused out before the time had a chance
to fire and show the label for the first time, then we check to see if the plug-in should
be displaying the label automatically, and if so, restart the timer using the longer delay.
(WebCore::RenderSnapshottedPlugIn::stopAndRestartDelayTimer): Convenience function to
update the m_showReason variable, and reset the timer with the appropriate delay.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@138927 268f45cc-cd09-0410-ab3c-d52691b4dbfc