Mac AVFoundation: use QTKit for cameras not working with AVF (Blackmagic).

media/video/capture/video_capture_device.h

Index: media/video/capture/video_capture_device.h
diff --git a/media/video/capture/video_capture_device.h b/media/video/capture/video_capture_device.h
index 4e060a1dcbe416ec8790edb6414748989742f011..8229716022a9bf261cfc4c7bd31481de6eb6edc4 100644
--- a/media/video/capture/video_capture_device.h
+++ b/media/video/capture/video_capture_device.h
@@ -48,12 +48,21 @@ class MEDIA_EXPORT VideoCaptureDevice {
       DIRECT_SHOW,
       API_TYPE_UNKNOWN
     };
-
+#endif
+#if defined(OS_MACOSX)
+    // Mac targets Capture Api type: it can only be set on construction.
+    enum CaptureApiType {
+      AVFOUNDATION,
+      QTKIT,
+      API_TYPE_UNKNOWN
+    };
+#endif
+#if defined(OS_WIN) || defined(OS_MACOSX)
     Name(const std::string& name,
          const std::string& id,
          const CaptureApiType api_type)
         : device_name_(name), unique_id_(id), capture_api_class_(api_type) {}
-#endif  // if defined(OS_WIN)
+#endif
     ~Name() {}
 
     // Friendly name of a device
@@ -63,7 +72,7 @@ class MEDIA_EXPORT VideoCaptureDevice {
     // friendly name connected to the computer this will be unique.
     const std::string& id() const { return unique_id_; }
 
-    // The unique hardware model identifier of the capture device.  Returns
+    // The unique hardware model identifier of the capture device. Returns
     // "[vid]:[pid]" when a USB device is detected, otherwise "".
     // The implementation of this method is platform-dependent.
     const std::string GetModel() const;
@@ -81,7 +90,7 @@ class MEDIA_EXPORT VideoCaptureDevice {
       return unique_id_ < other.id();
     }
 
-#if defined(OS_WIN)
+#if defined(OS_WIN) || defined(OS_MACOSX)
     CaptureApiType capture_api_type() const {
       return capture_api_class_.capture_api_type();
     }
@@ -90,16 +99,16 @@ class MEDIA_EXPORT VideoCaptureDevice {
    private:
     std::string device_name_;
     std::string unique_id_;
-#if defined(OS_WIN)
-    // This class wraps the CaptureApiType, so it has a by default value if not
-    // inititalized, and I (mcasas) do a DCHECK on reading its value.
+#if defined(OS_WIN) || defined(OS_MACOSX)
+    // This class wraps the CaptureApiType to give it a by default value if not
+    // initialized.
     class CaptureApiClass {
      public:
-      CaptureApiClass():  capture_api_type_(API_TYPE_UNKNOWN) {}
+      CaptureApiClass(): capture_api_type_(API_TYPE_UNKNOWN) {}
       CaptureApiClass(const CaptureApiType api_type)
-          :  capture_api_type_(api_type) {}
+          : capture_api_type_(api_type) {}
       CaptureApiType capture_api_type() const {
-        DCHECK_NE(capture_api_type_,  API_TYPE_UNKNOWN);
+        DCHECK_NE(capture_api_type_, API_TYPE_UNKNOWN);
         return capture_api_type_;
       }
      private:
@@ -107,7 +116,7 @@ class MEDIA_EXPORT VideoCaptureDevice {
     };
 
     CaptureApiClass capture_api_class_;
-#endif  // if defined(OS_WIN)
+#endif
     // Allow generated copy constructor and assignment.
   };