Fix 'ordered comparison between pointer and zero' errors

media/audio/win/audio_output_win_unittest.cc

Index: media/audio/win/audio_output_win_unittest.cc
diff --git a/media/audio/win/audio_output_win_unittest.cc b/media/audio/win/audio_output_win_unittest.cc
index 3e868546770ff39879806f6581354f163e062f22..8a131ac5afa972b947fad4e442bad8a39f53dee9 100644
--- a/media/audio/win/audio_output_win_unittest.cc
+++ b/media/audio/win/audio_output_win_unittest.cc
@@ -138,9 +138,7 @@ class ReadOnlyMappedFile {
     }
   }
   // Returns true if the file was successfully mapped.
-  bool is_valid() const {
-    return ((start_ > 0) && (size_ > 0));
-  }
+  bool is_valid() const { return (start_ && (size_ > 0)); }
   // Returns the size in bytes of the mapped memory.
   uint32_t size() const { return size_; }
   // Returns the memory backing the file.