Add a --enable-gesture-typing flag. Currently this flag does nothing.

ui/keyboard/keyboard_util.h

Index: ui/keyboard/keyboard_util.h
diff --git a/ui/keyboard/keyboard_util.h b/ui/keyboard/keyboard_util.h
index 3cbf9b6449a9bf1b977aef1d1162f81ce9a9024d..1f263a2356ae38ecf509e24505b5ce72c20c9722 100644
--- a/ui/keyboard/keyboard_util.h
+++ b/ui/keyboard/keyboard_util.h
@@ -96,6 +96,9 @@ KEYBOARD_EXPORT bool IsInputViewEnabled();
 // Returns true if experimental features are enabled for IME input-views.
 KEYBOARD_EXPORT bool IsExperimentalInputViewEnabled();
 
+// Returns true if gesture typing is enabled for virtual keyboard.
+KEYBOARD_EXPORT bool IsGestureTypingEnabled();
+
 // Insert |text| into the active TextInputClient if there is one. Returns true
 // if |text| was successfully inserted.
 KEYBOARD_EXPORT bool InsertText(const base::string16& text);