Fix error handling in POSIX version of the base::File::GetLength.

components/search_provider_logos/logo_cache_unittest.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 "components/search_provider_logos/logo_cache.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <string>
@@ skipping 76 matching lines @@
   ASSERT_TRUE(expected_logo.encoded_image.get());
   ASSERT_TRUE(actual_logo.encoded_image.get());
   EXPECT_TRUE(expected_logo.encoded_image->Equals(actual_logo.encoded_image));
   ExpectMetadataEqual(expected_logo.metadata, actual_logo.metadata);
 }
 
 // Removes 1 byte from the end of the file at |path|.
 void ShortenFile(base::FilePath path) {
   base::File file(path, base::File::FLAG_OPEN | base::File::FLAG_WRITE);
   int64_t file_length = file.GetLength();
-  ASSERT_NE(file_length, 0);
+  ASSERT_GT(file_length, 0);
   file.SetLength(file_length - 1);
 }
 
 class LogoCacheTest : public ::testing::Test {
  protected:
   void SetUp() override {
     ASSERT_TRUE(cache_parent_dir_.CreateUniqueTempDir());
     InitCache();
   }
 
@@ skipping 140 matching lines @@
   ExpectLogo(NULL);
   // Once the logo is noticed to be NULL, the metadata should also be cleared.
   ExpectMetadata(NULL);
 
   // Ensure corrupt cache files are deleted.
   EXPECT_FALSE(base::PathExists(cache_->GetMetadataPath()));
   EXPECT_FALSE(base::PathExists(cache_->GetLogoPath()));
 }
 
 }  // namespace search_provider_logos