Use fake media stream in ContentPreferencesTest#testCameraMicNotBlocked

chrome/android/java/src/org/chromium/chrome/ChromeSwitches.java

Index: chrome/android/java/src/org/chromium/chrome/ChromeSwitches.java
diff --git a/chrome/android/java/src/org/chromium/chrome/ChromeSwitches.java b/chrome/android/java/src/org/chromium/chrome/ChromeSwitches.java
index da0cc9fe99e9a40bdb32dc36e5321c5cb2c2b41c..82f4c09c3fda9fcfed9fd58dc476993e52dc0068 100644
--- a/chrome/android/java/src/org/chromium/chrome/ChromeSwitches.java
+++ b/chrome/android/java/src/org/chromium/chrome/ChromeSwitches.java
@@ -144,6 +144,13 @@ public abstract class ChromeSwitches {
      */
     public static final String GOOGLE_BASE_URL = "google-base-url";
 
+    /**
+     * Use fake device for Media Stream to replace actual camera and microphone.
+     * Native switch - switches::kUseFakeDeviceForMediaStream.
+     */
+    public static final String USE_FAKE_DEVICE_FOR_MEDIA_STREAM =
+            "use-fake-device-for-media-stream";
+
     // Prevent instantiation.
     private ChromeSwitches() {}
 }