Merge to XFA: Add path service to retrieve test data directory at run time so tests can be run from…

testing/embedder_test.h

Index: testing/embedder_test.h
diff --git a/testing/embedder_test.h b/testing/embedder_test.h
index 660acc386f170b2df91ef0c446a59105106e25c8..a5b5e33fae7834c767b28300420a402ab4406200 100644
--- a/testing/embedder_test.h
+++ b/testing/embedder_test.h
@@ -80,6 +80,8 @@ class EmbedderTest : public ::testing::Test,
 
   // Open the document specified by |filename|, and create its form fill
   // environment, or return false on failure.
+  // The filename is relative to the test data directory where we store all the
+  // test files.
   virtual bool OpenDocument(const std::string& filename);
 
   // Perform JavaScript actions that are to run at document open time.