Introduce "disable-speech-api" content flag and add it to WebView.

android_webview/lib/main/aw_main_delegate.cc

Index: android_webview/lib/main/aw_main_delegate.cc
diff --git a/android_webview/lib/main/aw_main_delegate.cc b/android_webview/lib/main/aw_main_delegate.cc
index 852081619f39e60952835d7157d8a053060609e0..7bafb44f0e39ba8b3182c238f5f695297d29c7d0 100644
--- a/android_webview/lib/main/aw_main_delegate.cc
+++ b/android_webview/lib/main/aw_main_delegate.cc
@@ -90,6 +90,9 @@ bool AwMainDelegate::BasicStartupComplete(int* exit_code) {
   // WebView does not yet support screen orientation locking.
   cl->AppendSwitch(switches::kDisableScreenOrientationLock);
 
+  // WebView does not currently support Web Speech API (crbug.com/483889)

[Peter Beverloo, 2015/05/07 16:45:24]

It'd be more useful to point to the bug which is about enabling Web Speech for
WebView.

[timvolodine, 2015/05/07 18:45:14]

do you mean "disabling"? is there such a bug or should it be created?

[Peter Beverloo, 2015/05/08 11:25:00]

No - if you look at other linked bugs, e.g. https://crbug.com/434712, they are
about adding support for the given feature to WebView.

I'd prefer if the bug in this comment could link to a bug that's about adding
support for the Web Speech API to WebView. If that bug doesn't exist yet, it
should be filed.

That way, people who stumble across this code and would like to know when it's
OK to remove the flag have a single place to go. The current bug would not be
updated when WebView starts supporting the speech APIs.

+  cl->AppendSwitch(switches::kDisableSpeechRecognition);
+
   // This is needed to be able to mmap the V8 snapshot and ICU data file
   // directly from the WebView .apk.
   // This needs to be here so that it gets to run before the code in