b/2449438 : ALT key sometimes doesn't work in the symbols keyboard

This change seems to fix it. Will continue to monitor if it happens.
From tracing the code, it seemed to think that the current keyboard
was not a symbols keyboard, so the "equals" call was failing. It was
probably due to voice mode changing between keyboard creation and
display.

src/com/android/inputmethod/latin/KeyboardSwitcher.java

@@ -147,8 +147,7 @@ public class KeyboardSwitcher {
         public boolean equals(KeyboardId other) {
           return other.mXml == this.mXml
               && other.mKeyboardMode == this.mKeyboardMode
-              && other.mEnableShiftLock == this.mEnableShiftLock
-              && other.mHasVoice == this.mHasVoice;
+              && other.mEnableShiftLock == this.mEnableShiftLock;
         }
 
         public int hashCode() {