Use PASS() everywhere in ppapi/tests.

ppapi/tests/test_image_data.cc

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ppapi/tests/test_image_data.h"
 
 #include "ppapi/cpp/graphics_2d.h"
 #include "ppapi/cpp/image_data.h"
 #include "ppapi/cpp/instance.h"
 #include "ppapi/cpp/module.h"
@@ skipping 19 matching lines @@
   pp::ImageData a(static_cast<PP_ImageDataFormat>(1337), pp::Size(16, 16),
                   true);
   if (!a.is_null())
     return "Crazy image data format accepted";
 
   pp::ImageData b(static_cast<PP_ImageDataFormat>(-1), pp::Size(16, 16),
                   true);
   if (!b.is_null())
     return "Negative image data format accepted";
 
-  return "";
+  PASS();
 }
 
 std::string TestImageData::TestInvalidSize() {
   pp::ImageData zero_size(PP_IMAGEDATAFORMAT_BGRA_PREMUL, pp::Size(0, 0), true);
   if (!zero_size.is_null())
     return "Zero width and height accepted";
 
   pp::ImageData zero_height(PP_IMAGEDATAFORMAT_BGRA_PREMUL,
                             pp::Size(16, 0), true);
   if (!zero_height.is_null())
@@ skipping 17 matching lines @@
   PP_Size negative_width;
   negative_width.width = -2;
   negative_width.height = 16;
   rsrc = image_data_interface_->Create(
       pp::Module::Get()->pp_module(),
       PP_IMAGEDATAFORMAT_BGRA_PREMUL,
       &negative_width, PP_TRUE);
   if (rsrc)
     return "Negative width accepted";
 
-  return "";
+  PASS();
 }
 
 std::string TestImageData::TestHugeSize() {
   pp::ImageData huge_size(PP_IMAGEDATAFORMAT_BGRA_PREMUL,
                           pp::Size(100000000, 100000000), true);
   if (!huge_size.is_null())
     return "31-bit overflow size accepted";
-  return "";
+  PASS();
 }
 
 std::string TestImageData::TestInitToZero() {
   const int w = 5;
   const int h = 6;
   pp::ImageData img(PP_IMAGEDATAFORMAT_BGRA_PREMUL, pp::Size(w, h), true);
   if (img.is_null())
     return "Could not create bitmap";
 
   // Basic validity checking of the bitmap. This also tests "describe" since
   // that's where the image data object got its imfo from.
   if (img.size().width() != w || img.size().height() != h)
     return "Wrong size";
   if (img.format() != PP_IMAGEDATAFORMAT_BGRA_PREMUL)
     return "Wrong format";
   if (img.stride() < w * 4)
     return "Stride too small";
 
   // Now check that everything is 0.
   for (int y = 0; y < h; y++) {
     uint32_t* row = img.GetAddr32(pp::Point(0, y));
     for (int x = 0; x < w; x++) {
       if (row[x] != 0)
         return "Image data isn't entirely zero";
     }
   }
 
-  return "";
+  PASS();
 }
 
 std::string TestImageData::TestIsImageData() {
   // Test that a NULL resource isn't an image data.
   pp::Resource null_resource;
   if (image_data_interface_->IsImageData(null_resource.pp_resource()))
     return "Null resource was reported as a valid image";
 
   // Make another resource type and test it.
   const int w = 16, h = 16;
   pp::Graphics2D device(pp::Size(w, h), true);
   if (device.is_null())
     return "Couldn't create device context";
   if (image_data_interface_->IsImageData(device.pp_resource()))
     return "Device context was reported as an image";
 
   // Make a valid image resource.
   pp::ImageData img(PP_IMAGEDATAFORMAT_BGRA_PREMUL, pp::Size(w, h), true);
   if (img.is_null())
     return "Couldn't create image data";
   if (!image_data_interface_->IsImageData(img.pp_resource()))
     return "Image data should be identified as an image";
 
-  return "";
+  PASS();
 }