Add missing (and remove superfluous) 'explicit' from constructors.

content/browser/device_orientation/provider_impl.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_DEVICE_ORIENTATION_PROVIDER_IMPL_H_
 #define CONTENT_BROWSER_DEVICE_ORIENTATION_PROVIDER_IMPL_H_
 
 #include <map>
 #include <set>
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "content/browser/device_orientation/data_fetcher.h"
 #include "content/browser/device_orientation/device_data.h"
 #include "content/browser/device_orientation/provider.h"
 #include "content/common/content_export.h"
 
 class MessageLoop;
 
 namespace content {
 
 class ProviderImpl : public Provider {
  public:
   typedef DataFetcher* (*DataFetcherFactory)();
 
   // Create a ProviderImpl that uses the factory to create a DataFetcher that
   // can provide data. A NULL DataFetcherFactory indicates that there are no
   // DataFetchers for this OS.
-  CONTENT_EXPORT ProviderImpl(DataFetcherFactory factory);
+  CONTENT_EXPORT explicit ProviderImpl(DataFetcherFactory factory);
 
   // From Provider.
   virtual void AddObserver(Observer* observer) OVERRIDE;
   virtual void RemoveObserver(Observer* observer) OVERRIDE;
 
  private:
   class PollingThread;
 
   virtual ~ProviderImpl();
 
@@ skipping 29 matching lines @@
   // Polling is done on this background thread. PollingThread is owned by
   // the ProviderImpl object. But its deletion doesn't happen synchronously
   // along with deletion of the ProviderImpl. Thus this should be a raw
   // pointer instead of scoped_ptr.
   PollingThread* polling_thread_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_DEVICE_ORIENTATION_PROVIDER_IMPL_H_