Mojo: Convert OVERRIDE -> override in various subdirectories of mojo/.

mojo/embedder/platform_channel_pair_posix_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 "mojo/embedder/platform_channel_pair.h"
 
 #include <errno.h>
 #include <poll.h>
 #include <signal.h>
 #include <stdio.h>
@@ skipping 26 matching lines @@
   pfds.fd = h.fd;
   pfds.events = POLLIN;
   CHECK_EQ(poll(&pfds, 1, -1), 1);
 }
 
 class PlatformChannelPairPosixTest : public testing::Test {
  public:
   PlatformChannelPairPosixTest() {}
   virtual ~PlatformChannelPairPosixTest() {}
 
-  virtual void SetUp() OVERRIDE {
+  virtual void SetUp() override {
     // Make sure |SIGPIPE| isn't being ignored.
     struct sigaction action = {};
     action.sa_handler = SIG_DFL;
     ASSERT_EQ(0, sigaction(SIGPIPE, &action, &old_action_));
   }
 
-  virtual void TearDown() OVERRIDE {
+  virtual void TearDown() override {
     // Restore the |SIGPIPE| handler.
     ASSERT_EQ(0, sigaction(SIGPIPE, &old_action_, nullptr));
   }
 
  private:
   struct sigaction old_action_;
 
   DISALLOW_COPY_AND_ASSIGN(PlatformChannelPairPosixTest);
 };
 
@@ skipping 181 matching lines @@
     char read_buf[100];
     size_t bytes_read = fread(read_buf, 1, sizeof(read_buf), fp.get());
     EXPECT_EQ(file_contents.size(), bytes_read);
     EXPECT_EQ(file_contents, std::string(read_buf, bytes_read));
   }
 }
 
 }  // namespace
 }  // namespace embedder
 }  // namespace mojo