Remove implicit conversions from scoped_refptr to T* in ash

This patch was generated by running the rewrite_scoped_refptr clang tool
on a ChromeOS build.

BUG=110610

Review URL: https://codereview.chromium.org/560223004

Cr-Commit-Position: refs/heads/master@{#294892}

ash/accelerometer/accelerometer_controller.cc

@@ -17,7 +17,8 @@ AccelerometerController::~AccelerometerController() {
 void AccelerometerController::Initialize(
     scoped_refptr<base::TaskRunner> blocking_task_runner) {
 #if defined(OS_CHROMEOS)
-  reader_.reset(new chromeos::AccelerometerReader(blocking_task_runner, this));
+  reader_.reset(
+      new chromeos::AccelerometerReader(blocking_task_runner.get(), this));
 #endif
 }