Fix bug #7148393 Switch can crash when hierarchyviewer is connected

Change-Id: I1713138a60358cc76f6cf373082a94199e85c717

Author: Fabrice Di Meglio

core/java/android/widget/Switch.java

@@ -750,10 +750,11 @@ protected void onDraw(Canvas canvas) {
         mTextPaint.drawableState = getDrawableState();
 
         Layout switchText = getTargetCheckedState() ? mOnLayout : mOffLayout;
-
-        canvas.translate((thumbLeft + thumbRight) / 2 - switchText.getWidth() / 2,
-                (switchInnerTop + switchInnerBottom) / 2 - switchText.getHeight() / 2);
-        switchText.draw(canvas);
+        if (switchText != null) {
+            canvas.translate((thumbLeft + thumbRight) / 2 - switchText.getWidth() / 2,
+                    (switchInnerTop + switchInnerBottom) / 2 - switchText.getHeight() / 2);
+            switchText.draw(canvas);
+        }
 
         canvas.restore();
     }