[GTK] Build GTK-specific, non-layer-violating source code into WebCore-independent libPlatformGtk.la
https://bugs.webkit.org/show_bug.cgi?id=112546

Reviewed by Martin Robinson.

.: 

* GNUmakefile.am: Define the new platform_webcore_cppflags.

Source/Platform: 

* GNUmakefile.am: Only specify the very minimal set of inclusion directories, containing the Source/WebCore/platform
directory and its subdirectories. This will allow only for the WebCore-independent GTK-specific sources to be built into
libPlatformGtk.la. Also include the GTK, libsecret and libsoup dependencies' cflags amongst the libPlatformGtk's
CPPFLAGS.
* GNUmakefile.list.am: Removed. The build targets are now listed (and will be listed until the migration) in the
GNUmakefile.list.am under Source/WebCore, following the common sense of specifying the build target in the
GNUmakefile.list.am placed in the same framework directory in which the source file is located.

Source/WebCore: 

No new tests - no new functionality.

* GNUmakefile.am: Passing the DATA_DIR value through the cppflags is not required anymore as the affected source is now
built into libPlatformGtk.la.
* GNUmakefile.list.am: Build the GTK-specific source files that are already independent of WebCore into the
libPlatformGtk.la by assigning the build targets listing to the platformgtk_sources variable.
* platform/gtk/GtkVersioning.c: Renamed from Source/Platform/gtk/GtkVersioning.c.
* platform/gtk/GtkVersioning.h: Renamed from Source/Platform/gtk/GtkVersioning.h.

Source/WebKit/gtk: 

* GNUmakefile.am: The GtkVersioning.c file has moved back under Source/WebCore/platform.

Source/WebKit2: 

* GNUmakefile.am: Reference the platform_webcore_cppflags and GTK, libsecret and libsoup dependencies' cflags amongst the
libPlatformGtk2's CPPFLAGS.
* Scripts/generate-forwarding-headers.pl: Remove the Platform framework from the list of the frameworks to be searched
for forwarding headers, it's at the moment not necessary to be included.
* Shared/gtk/ArgumentCodersGtk.cpp: Adjust the forwarding header for GtkVersioning.h that's been moved back under the
WebCore framework.
* Shared/gtk/WebEventFactory.cpp: Ditto.
* UIProcess/API/gtk/WebKitWebViewBase.cpp: Ditto.
* WebProcess/Plugins/Netscape/x11/NetscapePluginX11.cpp: Ditto.

Tools: 

* GNUmakefile.am: Reference the platformgtk_cppflags amongst the libWebCoreInternals' CPPFLAGS. GtkVersioning.c file has
moved back to Source/WebCore/platform. Fix an indentation issue as well.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@147137 268f45cc-cd09-0410-ab3c-d52691b4dbfc