Macro-based constraints

third_party/WebKit/public/platform/WebMediaConstraints.h

Index: third_party/WebKit/public/platform/WebMediaConstraints.h
diff --git a/third_party/WebKit/public/platform/WebMediaConstraints.h b/third_party/WebKit/public/platform/WebMediaConstraints.h
index b5175e973464936d2135f936efe5eaf1a2e291ac..17d2e1554c4c53baa58eeeaac6e5ad7519980d3b 100644
--- a/third_party/WebKit/public/platform/WebMediaConstraints.h
+++ b/third_party/WebKit/public/platform/WebMediaConstraints.h
@@ -236,23 +236,38 @@ private:
     unsigned m_hasExact : 1;
 };
 
+// This macro defines all the constraint names and their types.
+// The expansion of CONSTRAINT_ITEM will depend on context.
+#define CONSTRAINT_LIST \
+    CONSTRAINT_ITEM(width, Width, Long)    \
+    CONSTRAINT_ITEM(height, Height, Long)  \
+        CONSTRAINT_ITEM(aspectRatio, AspectRatio, Double) \
+        CONSTRAINT_ITEM(frameRate, FrameRate, Double) \
+        CONSTRAINT_ITEM(facingMode, FacingMode, String) \
+        CONSTRAINT_ITEM(volume, Volume, Double) \
+        CONSTRAINT_ITEM(sampleRate, SampleRate, Long) \
+        CONSTRAINT_ITEM(sampleSize, SampleSize, Long) \
+        CONSTRAINT_ITEM(echoCancellation, EchoCancellation, Boolean) \
+        CONSTRAINT_ITEM(latency, Latency, Double) \
+        CONSTRAINT_ITEM(channelCount, ChannelCount, Long) \
+        CONSTRAINT_ITEM(deviceId, DeviceId, String) \
+        CONSTRAINT_ITEM(groupId, GroupId, String)
+// End of list.
+// TODO(hta): Decide the future of the nonstandard constraints.
+// If they go forward, they need to be added here.
+// https://crbug.com/605673
+
 struct WebMediaTrackConstraintSet {
 public:
     BLINK_PLATFORM_EXPORT WebMediaTrackConstraintSet();
+    bool dummy; // added purely for init-call reasons
+#define CONSTRAINT_ITEM(lowercase, uppercase, datatype) \
+    datatype##Constraint lowercase;
+
+    CONSTRAINT_LIST
+
+#undef CONSTRAINT_ITEM
 
-    LongConstraint width;
-    LongConstraint height;
-    DoubleConstraint aspectRatio;
-    DoubleConstraint frameRate;
-    StringConstraint facingMode;
-    DoubleConstraint volume;
-    LongConstraint sampleRate;
-    LongConstraint sampleSize;
-    BooleanConstraint echoCancellation;
-    DoubleConstraint latency;
-    LongConstraint channelCount;
-    StringConstraint deviceId;
-    StringConstraint groupId;
     // Constraints not exposed in Blink at the moment, only through
     // the legacy name interface.
     StringConstraint mediaStreamSource; // tab, screen, desktop, system