Android SurfaceViewRenderer: Only clear image in release() if initialized

talk/app/webrtc/java/android/org/webrtc/SurfaceViewRenderer.java

Index: talk/app/webrtc/java/android/org/webrtc/SurfaceViewRenderer.java
diff --git a/talk/app/webrtc/java/android/org/webrtc/SurfaceViewRenderer.java b/talk/app/webrtc/java/android/org/webrtc/SurfaceViewRenderer.java
index 28404c9d6f13782562dd3d2c635e2a8a5e7defa4..b91d0866d3eb00bfe66b0d87921795989eb756f8 100644
--- a/talk/app/webrtc/java/android/org/webrtc/SurfaceViewRenderer.java
+++ b/talk/app/webrtc/java/android/org/webrtc/SurfaceViewRenderer.java
@@ -206,9 +206,11 @@ public class SurfaceViewRenderer extends SurfaceView
             GLES20.glDeleteTextures(3, yuvTextures, 0);
             yuvTextures = null;
           }
-          // Clear last rendered image to black.
-          GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
-          eglBase.swapBuffers();
+          if (eglBase.hasSurface()) {
+            // Clear last rendered image to black.
+            GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
+            eglBase.swapBuffers();
+          }
           eglBase.release();
           eglBase = null;
         }