Refactor how we handle resources path in Tests.

This idea emerged while doing https://codereview.chromium.org/321723002/
(commit 880914c35c8f7fc2e9c57134134c883baf66e538).

BUG=None
TEST=make tests && out/Debug/tests
R=mtklein@google.com

Author: tfarina@chromium.org

Review URL: https://codereview.chromium.org/346453002
diff --git a/gm/coloremoji.cpp b/gm/coloremoji.cpp
index 39c70bd..cf45008 100644
--- a/gm/coloremoji.cpp
+++ b/gm/coloremoji.cpp
@@ -6,6 +6,8 @@
  */
 
 #include "gm.h"
+
+#include "Resources.h"
 #include "SkCanvas.h"
 #include "SkStream.h"
 #include "SkTypeface.h"
@@ -27,8 +29,7 @@
     }
 
     virtual void onOnceBeforeDraw() SK_OVERRIDE {
-
-        SkString filename(INHERITED::gResourcePath);
+        SkString filename = GetResourcePath();
         filename.append("/Funkster.ttf");
 
         SkAutoTUnref<SkFILEStream> stream(new SkFILEStream(filename.c_str()));