Clean up histogram'd media enum max values.

media/base/sample_format.cc

Index: media/base/sample_format.cc
diff --git a/media/base/sample_format.cc b/media/base/sample_format.cc
index a4791cd6861ef5dbb86f0edfe0fa7ce2f0459383..011512ca4feceb3728cec2f2ba18ba7a576ea755 100644
--- a/media/base/sample_format.cc
+++ b/media/base/sample_format.cc
@@ -21,7 +21,7 @@ int SampleFormatToBytesPerChannel(SampleFormat sample_format) {
     case kSampleFormatF32:
     case kSampleFormatPlanarF32:
       return 4;
-    case kSampleFormatMax:
+    case kSampleFormatHistogramMax:
       break;
   }
 
@@ -45,7 +45,7 @@ const char* SampleFormatToString(SampleFormat sample_format) {
       return "Signed 16-bit planar";
     case kSampleFormatPlanarF32:
       return "Float 32-bit planar";
-    case kSampleFormatMax:
+    case kSampleFormatHistogramMax:
       break;
   }
   NOTREACHED() << "Invalid sample format provided: " << sample_format;