Adds missing function

Review URL: https://codereview.appspot.com/6346067

git-svn-id: http://skia.googlecode.com/svn/trunk@4459 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/debugger/SkDebugCanvas.h b/debugger/SkDebugCanvas.h
index e1bb2ab..4f3edb7 100644
--- a/debugger/SkDebugCanvas.h
+++ b/debugger/SkDebugCanvas.h
@@ -70,6 +70,13 @@
     std::vector<std::string>* getDrawCommandsAsStrings();
 
     /**
+        Returns length of draw command vector.
+     */
+    int getSize() {
+        return commandVector.size();
+    }
+
+    /**
         Toggles the execution of the draw command at index i.
      */
     void toggleCommand(int index);