<https://webkit.org/b/110410> Specify the plug-in process / service entitlements via the Xcode configuration.

This is the modern mechanism for applying entitlements to production builds,
and it simplifies the maintenance of entitlements going forward. It also allows
us to fix the new XPC PluginServices to have the same entitlements as PluginProcess.

Reviewed by Alexey Proskuryakov.

* Configurations/Base.xcconfig: Ad-hoc sign all WebKit2 components.
* Configurations/PluginProcess.xcconfig: Specify the entitlements to use.
* Configurations/PluginService.32.xcconfig: Ditto.
* Configurations/PluginService.64.xcconfig: Ditto.
* Configurations/PluginService.Development.xcconfig: Ditto.
* Configurations/PluginService.entitlements: Renamed from Source/WebKit2/PluginProcess/mac/PluginProcess.entitlements.
Move the entitlements in to the Configurations directory to make them easier to find.
* PluginProcess/mac/add-entitlements.sh: Removed. In my testing the dependency issue mentioned
in the script is not an issue with current versions of Xcode. If we see it again we can come
up with a workaround that doesn't involve performing the signing via a script phase.
* WebKit2.xcodeproj/project.pbxproj:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@143544 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Printing WebGL canvases in Chrome uses stale data after first print
https://bugs.webkit.org/show_bug.cgi?id=110003

Patch by Brandon Jones <bajones@google.com> on 2013-02-20
Reviewed by Kenneth Russell.

Unable to validate printed content automatically. No regression in existing WebGL tests.

 * html/canvas/WebGLRenderingContext.cpp:
 (WebCore):
 (WebCore::WebGLRenderingContext::paintRenderingResultsToCanvas):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@143545 268f45cc-cd09-0410-ab3c-d52691b4dbfc