Reland of Use spec-compliant algorithm to select video devices in getUserMedia.

content/public/android/java/src/org/chromium/content/common/ContentSwitches.java

Index: content/public/android/java/src/org/chromium/content/common/ContentSwitches.java
diff --git a/content/public/android/java/src/org/chromium/content/common/ContentSwitches.java b/content/public/android/java/src/org/chromium/content/common/ContentSwitches.java
index fc5cc565e9b1d7665ebf0777d8b81675e30265c6..a356d089e7e81271d1fdbaada1ab4b644407518c 100644
--- a/content/public/android/java/src/org/chromium/content/common/ContentSwitches.java
+++ b/content/public/android/java/src/org/chromium/content/common/ContentSwitches.java
@@ -74,6 +74,10 @@ public abstract class ContentSwitches {
     // Enable content intent detection in the renderer
     public static final String ENABLE_CONTENT_INTENT_DETECTION = "enable-content-intent-detection";
 
+    // Use fake device for Media Stream to replace actual camera and microphone.
+    public static final String USE_FAKE_DEVICE_FOR_MEDIA_STREAM =
+            "use-fake-device-for-media-stream";
+
     // Prevent instantiation.
     private ContentSwitches() {}