Merge pull request #153 from jianjunz/4.2.x

Merge to 4.2.x: change constraints setting value

Author: yanbin7

src/sdk/base/mediastream-factory.js

@@ -181,7 +181,11 @@ export class MediaStreamFactory {
         };
       }
     } else {
-      mediaConstraints.audio = constraints.audio;
+      if (constraints.audio.source === MediaFormatModule.AudioSourceInfo.SCREENCAST) {
+        mediaConstraints.audio = true;
+      } else {
+        mediaConstraints.audio = constraints.audio;
+      }
     }
     if (typeof constraints.audio === 'object' &&
         constraints.audio.source ===
@@ -198,12 +202,21 @@ export class MediaStreamFactory {
       if (constraints.video.resolution &&
           constraints.video.resolution.width &&
           constraints.video.resolution.height) {
-        mediaConstraints.video.width = Object.create({});
-        mediaConstraints.video.width.exact =
-            constraints.video.resolution.width;
-        mediaConstraints.video.height = Object.create({});
-        mediaConstraints.video.height.exact =
-            constraints.video.resolution.height;
+            if (constraints.video.source ===
+              MediaFormatModule.VideoSourceInfo.SCREENCAST) {
+              mediaConstraints.video.width =
+                constraints.video.resolution.width;
+              mediaConstraints.video.height =
+                constraints.video.resolution.height;
+            } else {
+              mediaConstraints.video.width = Object.create({});
+              mediaConstraints.video.width.exact =
+                  constraints.video.resolution.width;
+              mediaConstraints.video.height = Object.create({});
+              mediaConstraints.video.height.exact =
+                  constraints.video.resolution.height;
+
+            }
       }
       if (typeof constraints.video.deviceId === 'string') {
         mediaConstraints.video.deviceId = { exact: constraints.video.deviceId };