From 844d2b9670857b5bc2be88d9199d54ca870dc4b2 Mon Sep 17 00:00:00 2001
From: sakal <sakal@webrtc.org>
Date: Wed, 12 Apr 2017 01:27:44 -0700
Subject: [PATCH] Reconfigure capture session in a single transaction.

If we don't reconfigure capture session in a single transaction,
RTCCameraPreviewView goes transparent when switching cameras. This is
undesired behavior.

BUG=webrtc:7177

Review-Url: https://codereview.webrtc.org/2811643006
Cr-Commit-Position: refs/heads/master@{#17664}
---
 webrtc/sdk/objc/Framework/Classes/RTCCameraVideoCapturer.m | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/webrtc/sdk/objc/Framework/Classes/RTCCameraVideoCapturer.m b/webrtc/sdk/objc/Framework/Classes/RTCCameraVideoCapturer.m
index 6545b2f0d9..16ddc13c9e 100644
--- a/webrtc/sdk/objc/Framework/Classes/RTCCameraVideoCapturer.m
+++ b/webrtc/sdk/objc/Framework/Classes/RTCCameraVideoCapturer.m
@@ -378,6 +378,7 @@ static inline BOOL IsMediaSubTypeSupported(FourCharCode mediaSubType) {
     RTCLogError(@"Failed to create front camera input: %@", error.localizedDescription);
     return;
   }
+  [_captureSession beginConfiguration];
   for (AVCaptureDeviceInput *oldInput in [_captureSession.inputs copy]) {
     [_captureSession removeInput:oldInput];
   }
@@ -385,8 +386,8 @@ static inline BOOL IsMediaSubTypeSupported(FourCharCode mediaSubType) {
     [_captureSession addInput:input];
   } else {
     RTCLogError(@"Cannot add camera as an input to the session.");
-    return;
   }
+  [_captureSession commitConfiguration];
 }
 
 - (void)updateOrientation {