[EFL] Platform support for WebSpeech feature.
https://bugs.webkit.org/show_bug.cgi?id=116438

Reviewed by Csaba Osztrogonác.

.:
Add ENABLE_SPEECH_SYNTHESIS flag to have Speech Synthesis in EFL.

* Source/cmake/OptionsEfl.cmake:
* Source/cmake/WebKitFeatures.cmake:

Source/WebCore:
It's a first step of adding support for Speech Synthesis in EFL port.
Just stub out required API and support for compilation.

* CMakeLists.txt:
* PlatformEfl.cmake:
* PlatformGTK.cmake: Added some idls to not break GTK build.
* platform/PlatformSpeechSynthesizer.h:
* platform/efl/PlatformSpeechSynthesisProviderEfl.cpp: Added.
(WebCore::PlatformSpeechSynthesisProviderEfl::PlatformSpeechSynthesisProviderEfl):
(WebCore::PlatformSpeechSynthesisProviderEfl::~PlatformSpeechSynthesisProviderEfl):
(WebCore::PlatformSpeechSynthesisProviderEfl::initializeVoiceList):
(WebCore::PlatformSpeechSynthesisProviderEfl::pause):
(WebCore::PlatformSpeechSynthesisProviderEfl::resume):
(WebCore::PlatformSpeechSynthesisProviderEfl::speak):
(WebCore::PlatformSpeechSynthesisProviderEfl::cancel):
* platform/efl/PlatformSpeechSynthesisProviderEfl.h: Added.
* platform/efl/PlatformSpeechSynthesizerEfl.cpp: Added.
(WebCore::PlatformSpeechSynthesizer::PlatformSpeechSynthesizer):
(WebCore::PlatformSpeechSynthesizer::~PlatformSpeechSynthesizer):
(WebCore::PlatformSpeechSynthesizer::initializeVoiceList):
(WebCore::PlatformSpeechSynthesizer::pause):
(WebCore::PlatformSpeechSynthesizer::resume):
(WebCore::PlatformSpeechSynthesizer::speak):
(WebCore::PlatformSpeechSynthesizer::cancel):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@170288 268f45cc-cd09-0410-ab3c-d52691b4dbfc