Add onCameraDisconnected camera event.

BUG=webrtc:6334

Review-Url: https://codereview.webrtc.org/2381343002
Cr-Commit-Position: refs/heads/master@{#14540}

webrtc/api/android/java/src/org/webrtc/Camera1Session.java

@@ -202,8 +202,12 @@ public class Camera1Session implements CameraSession {
         Logging.e(TAG, errorMessage);
         state = SessionState.STOPPED;
         stopInternal();
+        if (error == android.hardware.Camera.CAMERA_ERROR_EVICTED) {
+          events.onCameraDisconnected(Camera1Session.this);
+        } else {
           events.onCameraError(Camera1Session.this, errorMessage);
         }
+      }
     });
 
     if (captureToTexture) {

webrtc/api/android/java/src/org/webrtc/Camera2Session.java

@@ -98,7 +98,14 @@ public class Camera2Session implements CameraSession {
     @Override
     public void onDisconnected(CameraDevice camera) {
       checkIsOnCameraThread();
-      reportError("Camera disconnected.");
+      final boolean startFailure = (captureSession == null);
+      state = SessionState.STOPPED;
+      stopInternal();
+      if (startFailure) {
+        callback.onFailure("Camera disconnected / evicted.");
+      } else {
+        events.onCameraDisconnected(Camera2Session.this);
+      }
     }
 
     @Override

webrtc/api/android/java/src/org/webrtc/CameraCapturer.java

@@ -118,6 +118,19 @@ public abstract class CameraCapturer implements CameraVideoCapturer {
       }
     }
 
+    @Override
+    public void onCameraDisconnected(CameraSession session) {
+      checkIsOnCameraThread();
+      synchronized (stateLock) {
+        if (session != currentSession) {
+          Logging.w(TAG, "onCameraDisconnected from another session.");
+          return;
+        }
+        eventsHandler.onCameraDisconnected();
+        stopCapture();
+      }
+    }
+
     @Override
     public void onCameraClosed(CameraSession session) {
       checkIsOnCameraThread();
@@ -204,6 +217,8 @@ public abstract class CameraCapturer implements CameraVideoCapturer {
         @Override
         public void onCameraError(String errorDescription) {}
         @Override
+        public void onCameraDisconnected() {}
+        @Override
         public void onCameraFreezed(String errorDescription) {}
         @Override
         public void onCameraOpening(String cameraName) {}

webrtc/api/android/java/src/org/webrtc/CameraSession.java

@@ -21,6 +21,7 @@ public interface CameraSession {
   public interface Events {
     void onCameraOpening();
     void onCameraError(CameraSession session, String error);
+    void onCameraDisconnected(CameraSession session);
     void onCameraClosed(CameraSession session);
     void onByteBufferFrameCaptured(
         CameraSession session, byte[] data, int width, int height, int rotation, long timestamp);

webrtc/api/android/java/src/org/webrtc/CameraVideoCapturer.java

@@ -25,6 +25,9 @@ public interface CameraVideoCapturer extends VideoCapturer {
     // or any camera exception happens on camera thread.
     void onCameraError(String errorDescription);
 
+    // Called when camera is disconnected.
+    void onCameraDisconnected();
+
     // Invoked when camera stops receiving frames.
     void onCameraFreezed(String errorDescription);
 

webrtc/api/android/java/src/org/webrtc/VideoCapturerAndroid.java

@@ -95,9 +95,13 @@ public class VideoCapturerAndroid
           }
           Logging.e(TAG, errorMessage);
           if (eventsHandler != null) {
+            if (error == android.hardware.Camera.CAMERA_ERROR_EVICTED) {
+              eventsHandler.onCameraDisconnected();
+            } else {
               eventsHandler.onCameraError(errorMessage);
             }
           }
+        }
       };
 
   public static VideoCapturerAndroid create(String name, CameraEventsHandler eventsHandler) {

webrtc/api/androidtests/src/org/webrtc/CameraVideoCapturerTestFixtures.java

@@ -195,6 +195,9 @@ class CameraVideoCapturerTestFixtures {
       cameraClosed = true;
     }
 
+    @Override
+    public void onCameraDisconnected() {}
+
     @Override
     public void onCameraFreezed(String errorDescription) {
       synchronized (onCameraFreezedLock) {