Mojo: Add a platform interface for shared memory (embedder::PlatformSharedBuffer).

mojo/system/raw_shared_buffer_win.cc

Index: mojo/system/raw_shared_buffer_win.cc
diff --git a/mojo/system/raw_shared_buffer_win.cc b/mojo/system/raw_shared_buffer_win.cc
index 14f9c2e16b6dfb7b4cb1ccb227aeaa368311fd66..8e2fcc4a7b9335ea19d137a631e892fc52761a44 100644
--- a/mojo/system/raw_shared_buffer_win.cc
+++ b/mojo/system/raw_shared_buffer_win.cc
@@ -57,8 +57,9 @@ bool RawSharedBuffer::InitFromPlatformHandle(
   return false;
 }
 
-scoped_ptr<RawSharedBufferMapping> RawSharedBuffer::MapImpl(size_t offset,
-                                                            size_t length) {
+scoped_ptr<embedder::PlatformSharedBufferMapping> RawSharedBuffer::MapImpl(
+    size_t offset,
+    size_t length) {
   size_t offset_rounding = offset % base::SysInfo::VMAllocationGranularity();
   size_t real_offset = offset - offset_rounding;
   size_t real_length = length + offset_rounding;
@@ -75,11 +76,11 @@ scoped_ptr<RawSharedBufferMapping> RawSharedBuffer::MapImpl(size_t offset,
                                   real_length);
   if (!real_base) {
     PLOG(ERROR) << "MapViewOfFile";
-    return scoped_ptr<RawSharedBufferMapping>();
+    return scoped_ptr<embedder::PlatformSharedBufferMapping>();
   }
 
   void* base = static_cast<char*>(real_base) + offset_rounding;
-  return make_scoped_ptr(
+  return scoped_ptr<embedder::PlatformSharedBufferMapping>(
       new RawSharedBufferMapping(base, length, real_base, real_length));
 }