Enable size_t to int truncation warnings in PPAPI

ppapi/shared_impl/array_writer.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 PPAPI_SHARED_IMPL_ARRAY_WRITER_H_
 #define PPAPI_SHARED_IMPL_ARRAY_WRITER_H_
 
 #include <string.h>
 
 #include <vector>
@@ skipping 56 matching lines @@
 
     if (input)
       memcpy(dest, input, sizeof(T) * count);
     return true;
   }
 
   // Copies the given array/vector of data to the plugin output array.  See
   // comment of StoreArray() for detail.
   template <typename T>
   bool StoreVector(const std::vector<T>& input) {
-    return StoreArray(input.size() ? &input[0] : NULL, input.size());
+    return StoreArray(input.size() ? &input[0] : NULL,
+                      static_cast<uint32_t>(input.size()));
   }
 
   // Stores the given vector of resources as PP_Resources to the output vector,
   // adding one reference to each.
   //
   // On failure this returns false, nothing will be copied, and the resource
   // refcounts will be unchanged. In either case, the object will become
   // is_null() immediately after the call since one output function should only
   // be issued once.
   //
@@ skipping 21 matching lines @@
 
  private:
   PP_ArrayOutput pp_array_output_;
 
   DISALLOW_COPY_AND_ASSIGN(ArrayWriter);
 };
 
 }  // namespace ppapi
 
 #endif  // PPAPI_SHARED_IMPL_ARRAY_WRITER_H_