Use PASS() everywhere in ppapi/tests.

ppapi/tests/test_url_util.cc

Index: ppapi/tests/test_url_util.cc
diff --git a/ppapi/tests/test_url_util.cc b/ppapi/tests/test_url_util.cc
index ea915062a081dd86baa61b46943b6ee2e39736bb..0f4e112e493910244745fa5299b095bdebd73d0d 100644
--- a/ppapi/tests/test_url_util.cc
+++ b/ppapi/tests/test_url_util.cc
@@ -65,7 +65,7 @@ std::string TestUrlUtil::TestCanonicalize() {
   ASSERT_TRUE(ComponentEquals(c.query, 0, -1));
   ASSERT_TRUE(ComponentEquals(c.ref, 0, -1));
 
-  return std::string();
+  PASS();
 }
 
 std::string TestUrlUtil::TestResolveRelative() {
@@ -92,7 +92,7 @@ std::string TestUrlUtil::TestResolveRelative() {
       ASSERT_TRUE(result.AsString() == test_cases[i].expected);
     }
   }
-  return std::string();
+  PASS();
 }
 
 std::string TestUrlUtil::TestIsSameSecurityOrigin() {
@@ -100,18 +100,18 @@ std::string TestUrlUtil::TestIsSameSecurityOrigin() {
                                            "http://example.com/"));
   ASSERT_TRUE(util_->IsSameSecurityOrigin("http://google.com/foo",
                                           "http://google.com/bar"));
-  return std::string();
+  PASS();
 }
 
 std::string TestUrlUtil::TestDocumentCanRequest() {
   // This is hard to test, but we can at least verify we can't request
   // some random domain.
   ASSERT_FALSE(util_->DocumentCanRequest(*instance_, "http://evil.com/"));
-  return std::string();
+  PASS();
 }
 
 std::string TestUrlUtil::TestDocumentCanAccessDocument() {
   // This is hard to test, but we can at least verify we can access ourselves.
   ASSERT_TRUE(util_->DocumentCanAccessDocument(*instance_, *instance_));
-  return std::string();
+  PASS();
 }