Clean up histogram'd media enum max values.

media/base/channel_mixer.cc

 // Copyright (c) 2012 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.
 
 // MSVC++ requires this to be set before any other includes to get M_SQRT1_2.
 #define _USE_MATH_DEFINES
 
 #include "media/base/channel_mixer.h"
 
 #include <algorithm>
 #include <cmath>
 
 #include "base/logging.h"
 #include "media/audio/audio_parameters.h"
 #include "media/base/audio_bus.h"
 #include "media/base/vector_math.h"
 
 namespace media {
 
 // Default scale factor for mixing two channels together.  We use a different
 // value for stereo -> mono and mono -> stereo mixes.
 static const float kEqualPowerScale = static_cast<float>(M_SQRT1_2);
 
 static void ValidateLayout(ChannelLayout layout) {
   CHECK_NE(layout, CHANNEL_LAYOUT_NONE);
-  CHECK_NE(layout, CHANNEL_LAYOUT_MAX);
+  CHECK_LE(layout, CHANNEL_LAYOUT_MAX);
   CHECK_NE(layout, CHANNEL_LAYOUT_UNSUPPORTED);
   CHECK_NE(layout, CHANNEL_LAYOUT_DISCRETE);
 
   // Verify there's at least one channel.  Should always be true here by virtue
   // of not being one of the invalid layouts, but lets double check to be sure.
   int channel_count = ChannelLayoutToChannelCount(layout);
   DCHECK_GT(channel_count, 0);
 
   // If we have more than one channel, verify a symmetric layout for sanity.
   // The unit test will verify all possible layouts, so this can be a DCHECK.
@@ skipping 126 matching lines @@
     // If the number of input channels is less than output channels, then
     // copy them all, then zero out the remaining output channels.
     int passthrough_channels = std::min(input_channels_, output_channels_);
     for (int i = 0; i < passthrough_channels; ++i)
       (*matrix_)[i][i] = 1;
 
     return true;
   }
 
   // Route matching channels and figure out which ones aren't accounted for.
-  for (Channels ch = LEFT; ch < CHANNELS_MAX;
+  for (Channels ch = LEFT; ch < CHANNELS_MAX + 1;
        ch = static_cast<Channels>(ch + 1)) {
     int input_ch_index = ChannelOrder(input_layout_, ch);
     if (input_ch_index < 0)
       continue;
 
     int output_ch_index = ChannelOrder(output_layout_, ch);
     if (output_ch_index < 0) {
       unaccounted_inputs_.push_back(ch);
       continue;
     }
@@ skipping 213 matching lines @@
 
   DCHECK(IsUnaccounted(input_ch));
   DCHECK_GE(input_ch_index, 0);
   DCHECK_GE(output_ch_index, 0);
 
   DCHECK_EQ((*matrix_)[output_ch_index][input_ch_index], 0);
   (*matrix_)[output_ch_index][input_ch_index] = scale;
 }
 
 }  // namespace media