Add WARN_UNUSED_RESULT to base::Time methods that return bool.

chrome/browser/chromeos/file_system_provider/operations/get_metadata.cc

 // Copyright 2014 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 "chrome/browser/chromeos/file_system_provider/operations/get_metadata.h"
 
 #include <stdint.h>
 
 #include <algorithm>
 #include <string>
 #include <utility>
 
+#include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "chrome/common/extensions/api/file_system_provider.h"
 #include "chrome/common/extensions/api/file_system_provider_internal.h"
 
 namespace chromeos {
 namespace file_system_provider {
 namespace operations {
 namespace {
 
 // Convert |value| into |output|. If parsing fails, then returns false.
@@ skipping 23 matching lines @@
         new int64_t(static_cast<int64_t>(*params->metadata.size)));
 
   if (fields & ProvidedFileSystemInterface::METADATA_FIELD_MODIFICATION_TIME) {
     std::string input_modification_time;
     params->metadata.modification_time->additional_properties.GetString(
         "value", &input_modification_time);
 
     // Allow to pass invalid modification time, since there is no way to verify
     // it easily on any earlier stage.
     base::Time output_modification_time;
-    base::Time::FromString(input_modification_time.c_str(),
-                           &output_modification_time);
+    ignore_result(base::Time::FromString(input_modification_time.c_str(),
+                                         &output_modification_time));
     output->modification_time.reset(new base::Time(output_modification_time));
   }
 
   if (fields & ProvidedFileSystemInterface::METADATA_FIELD_MIME_TYPE &&
       params->metadata.mime_type.get()) {
     output->mime_type.reset(new std::string(*params->metadata.mime_type.get()));
   }
 
   if (fields & ProvidedFileSystemInterface::METADATA_FIELD_THUMBNAIL &&
       params->metadata.thumbnail.get()) {
@@ skipping 126 matching lines @@
 
 void GetMetadata::OnError(int /* request_id */,
                           std::unique_ptr<RequestValue> /* result */,
                           base::File::Error error) {
   callback_.Run(base::WrapUnique<EntryMetadata>(NULL), error);
 }
 
 }  // namespace operations
 }  // namespace file_system_provider
 }  // namespace chromeos