Incorporate BlobChannel into Blimp image encode/decode pipeline.

blimp/net/browser_connection_handler.cc

Index: blimp/net/browser_connection_handler.cc
diff --git a/blimp/net/browser_connection_handler.cc b/blimp/net/browser_connection_handler.cc
index 37519f7b9db40ca747886ab306e11324ba40367b..827f95d10c7f07b3ef413c621df074cf69bd36f2 100644
--- a/blimp/net/browser_connection_handler.cc
+++ b/blimp/net/browser_connection_handler.cc
@@ -63,7 +63,10 @@ void BrowserConnectionHandler::OnConnectionError(int error) {
 }
 
 void BrowserConnectionHandler::DropCurrentConnection() {
-  DCHECK(connection_);
+  if (!connection_) {
+    return;
+  }
+
   output_buffer_->SetOutputProcessor(nullptr);
   connection_.reset();
 }