Added WARN_UNUSED_RESULT to ScopedTempDir methods.

chrome/test/automation/automation_proxy_uitest.cc

 // Copyright (c) 2011 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 <string>
 
 #include "app/app_switches.h"
 #include "app/message_box_flags.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
@@ skipping 1557 matching lines @@
   std::wstring jscript = CreateJSString(L"\"" + expected + L"\"");
   std::wstring actual;
   ASSERT_TRUE(tab->ExecuteAndExtractString(L"", jscript, &actual));
   ASSERT_EQ(expected, actual);
 }
 
 class AutomationProxySnapshotTest : public UITest {
  protected:
   AutomationProxySnapshotTest() {
     dom_automation_enabled_ = true;
-    snapshot_dir_.CreateUniqueTempDir();
-    snapshot_path_ = snapshot_dir_.path().AppendASCII("snapshot.png");
+    if (!snapshot_dir_.CreateUniqueTempDir())
+      ADD_FAILURE() << "Unable to create temporary directory";
+    else
+      snapshot_path_ = snapshot_dir_.path().AppendASCII("snapshot.png");
   }
 
   // Asserts that the given png file can be read and decoded into the given
   // bitmap.
   void AssertReadPNG(const FilePath& filename, SkBitmap* bitmap) {
     DCHECK(bitmap);
     ASSERT_TRUE(file_util::PathExists(filename));
 
     int64 size64;
     ASSERT_TRUE(file_util::GetFileSize(filename, &size64));
@@ skipping 157 matching lines @@
   int diff_pixels_count = 0;
   for (int x = 0; x < img_size.width(); ++x) {
     for (int y = 0; y < img_size.height(); ++y) {
       if (*snapshot_bmp.getAddr32(x, y) != *reference_bmp.getAddr32(x, y)) {
         ++diff_pixels_count;
       }
     }
   }
   ASSERT_EQ(diff_pixels_count, 0);
 }