https://bugs.webkit.org/show_bug.cgi?id=115548

Reviewed by Dean Jackson.

Source/WebCore:

* Resources/plugIns.js:
(createOverlay):
Implement the createOverlay(shadowRoot, titleText, subtitleText) method
that is called from WebCore (HTMLPlugInImageElement::didAddUserAgentShadowRoot)
to allow the injected script to customize the shadow root for a snapshotted
plug-in. This is a default implementation, clients are expected to customize
this by providing their own JS file with enhanced behavior.

* css/CSSDefaultStyleSheets.cpp:
(WebCore::CSSDefaultStyleSheets::ensureDefaultStyleSheetsForElement):
Since we no longer have a default shadow tree generated in C++, it makes little
sense for clients to extend the default snapshotted plug-in stylesheet, so we
only insert it if no custom one is provided by the chrome client.

* css/plugIns.css:
Better styling of the default snapshotted plug-in overlay look by using CSS
flex boxes. Also using more explicit selector as an optimization.

* dom/Document.cpp:
(WebCore::Document::ensurePlugInsInjectedScript):
Expose a new method to allow HTMLPlugInImageElement instances to ensure that
the JavaScript code required to customize the snapshotted plug-in's shadow root
is indeed injected in the current document. The actual injection would only
happen once per document so all snapshotted plug-ins share the same scripting
context.

* dom/Document.h:
Expose the new ensurePlugInsInjectedScript method and the m_hasInjectedPlugInsScript
property used to ensure injection happens only once per document.

* html/HTMLPlugInImageElement.cpp:
(WebCore::titleText):
(WebCore::subtitleText):
Store the localized strings for each mime-type in a static hash map as it can be
costly to retrieve them each time from the client. It is expected the chrome client
will want to provide localized strings taking into account the snapshotted plug-in's
mime-type, so we're adding this as a parameter.
(WebCore::HTMLPlugInImageElement::checkSnapshotStatus):
Dispatch a "resize" event to the shadow root to notify the injected script that the
snapshotted plug-in's metrics have changed and to allow the overlay to update itself
as a result.
(WebCore::HTMLPlugInImageElement::didAddUserAgentShadowRoot):
Remove all the DOM generation code in favor of an approach where we create a shared
DOM scripting world in which we inject JavaScript code that will perform the same
task but will additionally be provided by the client in order to provide a completely
custom overlay for the snapshotted plug-in. The sole contract is for the JavaScript
to implement a createOverlay(shadowRoot, titleText, subtitleText) method.
(WebCore::HTMLPlugInImageElement::partOfSnapshotOverlay):
Renamed method to be generic to the overlay as opposed to text labels and use the
element with CSS class name "snapshot-overlay" as the comparison node.

* html/HTMLPlugInImageElement.h:
(HTMLPlugInImageElement):
Removing a couple of unused members since we no longer generate the shadow DOM from C++
and rename the partOfSnapshotLabel method to partOfSnapshotOverlay.

* page/ChromeClient.h:
(WebCore::ChromeClient::plugInStartLabelTitle):
(WebCore::ChromeClient::plugInStartLabelSubtitle):
(WebCore::ChromeClient::plugInExtraScript):
Pass in the mime-type to plugInStartLabelTitle and plugInStartLabelSubtitle and expose
a new plugInExtraScript method to allow the chrome client to provide a custom JS file
for the management of the shadow root.

* rendering/RenderSnapshottedPlugIn.cpp:
(WebCore::RenderSnapshottedPlugIn::handleEvent):
Update the terminology from "label" to "overlay" per the changes made in HTMLPlugInImageElement.

Source/WebKit2:

Expose a new plugInExtraScript method to support the injection of
a JS file from the chrome client to customize the rendering of a
snapshotted plug-in's shadow tree. Additionally, it is expected
the chrome client will want to provide localized strings taking
into account the snapshotted plug-in's mime-type, so we're adding
this as a parameter to both plugInStartLabelTitle and
plugInStartLabelSubtitle methods.

* WebProcess/InjectedBundle/API/c/WKBundlePage.h:
* WebProcess/InjectedBundle/InjectedBundlePageUIClient.cpp:
(WebKit::InjectedBundlePageUIClient::plugInStartLabelTitle):
(WebKit::InjectedBundlePageUIClient::plugInStartLabelSubtitle):
(WebKit::InjectedBundlePageUIClient::plugInExtraScript):
* WebProcess/InjectedBundle/InjectedBundlePageUIClient.h:
(InjectedBundlePageUIClient):
* WebProcess/WebCoreSupport/WebChromeClient.cpp:
(WebKit::WebChromeClient::plugInStartLabelTitle):
(WebKit::WebChromeClient::plugInStartLabelSubtitle):
(WebKit::WebChromeClient::plugInExtraScript):
* WebProcess/WebCoreSupport/WebChromeClient.h:
(WebChromeClient):

Tools:

Take into account the new plugInExtraScript method added to support
the injection of a JS file from the chrome client to customize the
rendering of a snapshotted plug-in's shadow tree.

* WebKitTestRunner/InjectedBundle/InjectedBundlePage.cpp:
(WTR::InjectedBundlePage::InjectedBundlePage):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@149586 268f45cc-cd09-0410-ab3c-d52691b4dbfc