<rdar://problem/8559439>
https://bugs.webkit.org/show_bug.cgi?id=48701

Reviewed by Anders Carlsson.

Port WebCore's PopupMenuWin's implementation to work within the confines of WebKit2.
Since we currently can't draw text using WebCore in the UIProcess, this approach uses
the WebProcess to create two bitmaps representing the full popup menu (both unselected and 
selected) and sends them to the UIProcess to be drawn in an HWND.

* Shared/BackingStore.h:
* Shared/cg/BackingStoreCG.cpp:
* Shared/qt/BackingStoreQt.cpp:

Add new function to create a flipped graphics context from the backing store, 
and add additional parameters to paint, to allow more control of how the backing
store is painted into the destination context.

* Shared/PlatformPopupMenuData.cpp: Added.
(WebKit::PlatformPopupMenuData::PlatformPopupMenuData):
(WebKit::PlatformPopupMenuData::encode):
(WebKit::PlatformPopupMenuData::decode):
* Shared/PlatformPopupMenuData.h: Added.
Add struct so platforms can send platform specific data to their popup menu implementations.

* Shared/WebPopupItem.cpp:
(WebKit::WebPopupItem::WebPopupItem):
(WebKit::WebPopupItem::encode):
(WebKit::WebPopupItem::decode):
* Shared/WebPopupItem.h:
Add isLabel for each menu item.

* UIProcess/FindIndicator.cpp:
(WebKit::FindIndicator::draw):
Update for new BackingStore::paint signature.

* UIProcess/WebPageProxy.cpp:
(WebKit::WebPageProxy::showPopupMenu):
* UIProcess/WebPageProxy.h:
* UIProcess/WebPageProxy.messages.in:
* UIProcess/WebPopupMenuProxy.h:
* UIProcess/mac/WebPopupMenuProxyMac.h:
* UIProcess/mac/WebPopupMenuProxyMac.mm:
(WebKit::WebPopupMenuProxyMac::showPopupMenu):
* UIProcess/qt/WebPopupMenuProxyQt.cpp:
(WebKit::WebPopupMenuProxyQt::showPopupMenu):
* UIProcess/qt/WebPopupMenuProxyQt.h:
Pass through the new PlatformPopupMenuData.

* UIProcess/win/WebPopupMenuProxyWin.cpp:
* UIProcess/win/WebPopupMenuProxyWin.h:
Port implementation from WebCore.

* UIProcess/win/WebView.cpp:
(WebKit::WebView::createPopupMenuProxy):
Pass the WebView to the WebPopupMenuProxyWin.

* WebProcess/Plugins/PluginProxy.cpp:
(WebKit::PluginProxy::paint):
(WebKit::PluginProxy::update):
Update for new BackingStore::paint signature.

* WebProcess/WebCoreSupport/WebPopupMenu.cpp:
(WebKit::WebPopupMenu::populateItems): Add isLabel for each item.
(WebKit::WebPopupMenu::show): Give each platform a chance to add platform specific data.
* WebProcess/WebCoreSupport/WebPopupMenu.h:

* WebProcess/WebCoreSupport/mac/WebPopupMenuMac.mm: Added.
(WebKit::WebPopupMenu::setUpPlatformData):
* WebProcess/WebCoreSupport/qt/WebPopupMenuQt.cpp: Added.
(WebKit::WebPopupMenu::setUpPlatformData):
Add stubbed out setUpPlatformData.

* WebProcess/WebCoreSupport/win/WebPopupMenuWin.cpp: Added.
(WebKit::WebPopupMenu::setUpPlatformData):
Compute data needed in the UIProcess including generating the bitmaps.

* WebKit2.pro:
* WebKit2.xcodeproj/project.pbxproj:
* win/WebKit2.vcproj:
Add new files.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@71640 268f45cc-cd09-0410-ab3c-d52691b4dbfc