[Video Capture, Android] Fix more nullptr exceptions

Method getCameraParameters() in file VideoCaptureCamera.java may return
null on failure. But several call sites assume that this never happens.
Crash reports show that it does happen.

This CL adds null checks and performs the appropriate failure action.

Bug: 879678
Change-Id: I978f45c04696c9a5b272932a945da033bafc6a77
Reviewed-on: https://chromium-review.googlesource.com/1214072Reviewed-by: Emircan Uysaler <emircan@chromium.org>
Commit-Queue: Christian Fremerey <chfremer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#590007}

media/capture/video/android/java/src/org/chromium/media/VideoCapture.java

@@ -75,7 +75,8 @@ public abstract class VideoCapture {
     @CalledByNative
     public abstract boolean stopCaptureAndBlockUntilStopped();
 
-    // Replies by calling nativeOnGetPhotoCapabilitiesReply().
+    // Replies by calling nativeOnGetPhotoCapabilitiesReply(). Will pass |null|
+    // for parameter |result| to indicate failure.
     @CalledByNative
     public abstract void getPhotoCapabilitiesAsync(long callbackId);
 

media/capture/video/android/java/src/org/chromium/media/VideoCaptureCamera.java

@@ -484,6 +484,10 @@ public class VideoCaptureCamera
     @Override
     public void getPhotoCapabilitiesAsync(long callbackId) {
         final android.hardware.Camera.Parameters parameters = getCameraParameters(mCamera);
+        if (parameters == null) {
+            nativeOnGetPhotoCapabilitiesReply(mNativeVideoCaptureDeviceAndroid, callbackId, null);
+            return;
+        }
         PhotoCapabilities.Builder builder = new PhotoCapabilities.Builder();
         Log.i(TAG, " CAM params: %s", parameters.flatten());
 
@@ -646,6 +650,9 @@ public class VideoCaptureCamera
             double iso, boolean hasRedEyeReduction, boolean redEyeReduction, int fillLightMode,
             boolean hasTorch, boolean torch, double colorTemperature) {
         android.hardware.Camera.Parameters parameters = getCameraParameters(mCamera);
+        if (parameters == null) {
+            return;
+        }
 
         if (parameters.isZoomSupported() && zoom > 0) {
             // |zoomRatios| is an ordered list; need the closest zoom index for parameters.setZoom()
@@ -794,8 +801,16 @@ public class VideoCaptureCamera
             mPhotoTakenCallbackId = callbackId;
         }
         mPreviewParameters = getCameraParameters(mCamera);
+        if (mPreviewParameters == null) {
+            notifyTakePhotoError(callbackId);
+            return;
+        }
 
         android.hardware.Camera.Parameters photoParameters = getCameraParameters(mCamera);
+        if (photoParameters == null) {
+            notifyTakePhotoError(callbackId);
+            return;
+        }
         photoParameters.setRotation(getCameraRotation());
 
         if (mPhotoWidth > 0 || mPhotoHeight > 0) {

media/capture/video/android/video_capture_device_android.cc

@@ -385,6 +385,10 @@ void VideoCaptureDeviceAndroid::OnGetPhotoCapabilitiesReply(
     NOTREACHED() << "|callback_id| not found.";
     return;
   }
+  if (result == nullptr) {
+    get_photo_state_callbacks_.erase(reference_it);
+    return;
+  }
 
   base::android::ScopedJavaLocalRef<jobject> scoped_photo_capabilities(env,
                                                                        result);