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

Source/WebKit/chromium/src/WebRuntimeFeatures.cpp

Index: Source/WebKit/chromium/src/WebRuntimeFeatures.cpp
diff --git a/Source/WebKit/chromium/src/WebRuntimeFeatures.cpp b/Source/WebKit/chromium/src/WebRuntimeFeatures.cpp
index f263e2c390e070ba5d5accbfb29a8514cbb245e0..bb56d0a355a0cf2661c8046e91641b4a9e6eb87b 100644
--- a/Source/WebKit/chromium/src/WebRuntimeFeatures.cpp
+++ b/Source/WebKit/chromium/src/WebRuntimeFeatures.cpp
@@ -500,4 +500,14 @@ bool WebRuntimeFeatures::isIMEAPIEnabled()
     return RuntimeEnabledFeatures::imeAPIEnabled();
 }
 
+void WebRuntimeFeatures::enableSpeechSynthesis(bool enable)
+{
+    RuntimeEnabledFeatures::setSpeechSynthesisEnabled(enable);
+}
+
+bool WebRuntimeFeatures::isSpeechSynthesisEnabled()
+{
+    return RuntimeEnabledFeatures::speechSynthesisEnabled();
+}
+
 } // namespace WebKit