Change the media::PowerLineFrequency from an enum class to a proper class

media/base/video_capture_types.h

Index: media/base/video_capture_types.h
diff --git a/media/base/video_capture_types.h b/media/base/video_capture_types.h
index 4790ea52e1e12414226a882142495ed03c4b3eaa..2f5098676e894f5ba79c11838c7478abbd3a4b83 100644
--- a/media/base/video_capture_types.h
+++ b/media/base/video_capture_types.h
@@ -55,12 +55,25 @@ enum ResolutionChangePolicy {
 // Potential values of the googPowerLineFrequency optional constraint passed to
 // getUserMedia. Note that the numeric values are currently significant, and are
 // used to map enum values to corresponding frequency values.
-// TODO(ajose): http://crbug.com/525167 Consider making this a class.
-enum class PowerLineFrequency {
-  FREQUENCY_DEFAULT = 0,
-  FREQUENCY_50HZ = 50,
-  FREQUENCY_60HZ = 60,
-  FREQUENCY_MAX = FREQUENCY_60HZ
+class MEDIA_EXPORT PowerLineFrequency {
+private:

[wolenetz, 2015/09/09 19:39:15]

public before private:
http://google-styleguide.googlecode.com/svn/trunk/cppguide.html#Declaration_O...

[suvanjanmukherjee, 2015/09/13 15:33:46]

Done.

+  int freq_;
+
+  void check(int freq);

[wolenetz, 2015/09/09 19:39:15]

methods before data members:
http://google-styleguide.googlecode.com/svn/trunk/cppguide.html#Declaration_O...

[suvanjanmukherjee, 2015/09/13 15:33:46]

Done.

+public:
+  // Static members
+  static constexpr int FREQUENCY_DEFAULT = 0;

[wolenetz, 2015/09/09 19:39:15]

constexpr usage is currently banned in Chromium (see
http://chromium-cpp.appspot.com/)

[suvanjanmukherjee, 2015/09/13 15:33:46]

Done.

+  static constexpr int FREQUENCY_50HZ = 50;
+  static constexpr int FREQUENCY_60HZ = 60;
+  static constexpr int FREQUENCY_MAX = FREQUENCY_60HZ;
+
+  // Functions
+  PowerLineFrequency(int freq);

[wolenetz, 2015/09/09 19:39:15]

use "explicit"

[suvanjanmukherjee, 2015/09/13 15:33:46]

Done.

+  PowerLineFrequency& operator = (int freq);

[wolenetz, 2015/09/09 19:39:15]

For this and the next line, use consistent and correct whitespace.

[suvanjanmukherjee, 2015/09/13 15:33:46]

Done.

+  PowerLineFrequency& operator =(const PowerLineFrequency& rhs);
+
+  // Automatically cast to int
+  operator int() const;
 };
 // Assert that the int:frequency mapping is correct.
 static_assert(static_cast<int>(PowerLineFrequency::FREQUENCY_DEFAULT) == 0,

[ajose, 2015/09/10 17:24:55]

Remove static_casts?

[suvanjanmukherjee, 2015/09/13 15:33:46]

Done.