chrome.bluetoothSocket: Fix regression in send()

In https://crrev.com/c/997098, params_ was changed to a local variable,
but it needs to last longer than that since net::WrappedIOBuffer may use
the data after the local variable goes out of scope.

This CL changed it back to be an instance variable.

Bug: 851799
Change-Id: I392f8acaef4c6473d6ea4fbee7209445aa09112e
Reviewed-on: https://chromium-review.googlesource.com/1103676Reviewed-by: Toni Barzic <tbarzic@chromium.org>
Commit-Queue: Sonny Sasaka <sonnysasaka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#568137}

extensions/browser/api/bluetooth_socket/bluetooth_socket_api.cc

@@ -545,13 +545,13 @@ BluetoothSocketSendFunction::~BluetoothSocketSendFunction() {}
 ExtensionFunction::ResponseAction BluetoothSocketSendFunction::Run() {
   DCHECK_CURRENTLY_ON(work_thread_id());
 
-  auto params = bluetooth_socket::Send::Params::Create(*args_);
-  EXTENSION_FUNCTION_VALIDATE(params.get());
+  params_ = bluetooth_socket::Send::Params::Create(*args_);
+  EXTENSION_FUNCTION_VALIDATE(params_.get());
 
-  io_buffer_size_ = params->data.size();
-  io_buffer_ = new net::WrappedIOBuffer(params->data.data());
+  io_buffer_size_ = params_->data.size();
+  io_buffer_ = new net::WrappedIOBuffer(params_->data.data());
 
-  BluetoothApiSocket* socket = GetSocket(params->socket_id);
+  BluetoothApiSocket* socket = GetSocket(params_->socket_id);
   if (!socket)
     return RespondNow(Error(kSocketNotFoundError));
 

extensions/browser/api/bluetooth_socket/bluetooth_socket_api.h

@@ -294,6 +294,7 @@ class BluetoothSocketSendFunction : public BluetoothSocketAsyncApiFunction {
   void OnError(BluetoothApiSocket::ErrorReason reason,
                const std::string& message);
 
+  std::unique_ptr<bluetooth_socket::Send::Params> params_;
   scoped_refptr<net::IOBuffer> io_buffer_;
   size_t io_buffer_size_;