Switch speech synthesis from compile-flag to runtime-flag.

Source/core/platform/PlatformSpeechSynthesisVoice.cpp

Index: Source/core/platform/PlatformSpeechSynthesisVoice.cpp
diff --git a/Source/core/platform/PlatformSpeechSynthesisVoice.cpp b/Source/core/platform/PlatformSpeechSynthesisVoice.cpp
index 95553f9a685d24bc38a697048304b6684f8db304..432de7bc5e181fc6879518273e6520b53a24db2b 100644
--- a/Source/core/platform/PlatformSpeechSynthesisVoice.cpp
+++ b/Source/core/platform/PlatformSpeechSynthesisVoice.cpp
@@ -26,8 +26,6 @@
 #include "config.h"
 #include "core/platform/PlatformSpeechSynthesisVoice.h"
 
-#if ENABLE(SPEECH_SYNTHESIS)
-
 namespace WebCore {
 
 PassRefPtr<PlatformSpeechSynthesisVoice> PlatformSpeechSynthesisVoice::create(const String& voiceURI, const String& name, const String& lang, bool localService, bool isDefault)
@@ -56,5 +54,3 @@ PlatformSpeechSynthesisVoice::PlatformSpeechSynthesisVoice()
 }
 
 } // namespace WebCore
-
-#endif // ENABLE(SPEECH_SYNTHESIS)