Add compile time checks against longs being used in IPC structs on 32 bit Android.

content/child/webblobregistry_impl.cc

Index: content/child/webblobregistry_impl.cc
diff --git a/content/child/webblobregistry_impl.cc b/content/child/webblobregistry_impl.cc
index ecdc0fcf4b9051c100bcf2629239c1b0c3b79db6..65a1246b3675e5f105859abf3374cd733febdbb5 100644
--- a/content/child/webblobregistry_impl.cc
+++ b/content/child/webblobregistry_impl.cc
@@ -154,7 +154,7 @@ void WebBlobRegistryImpl::addDataToStream(const WebURL& url,
       size_t chunk_size = std::min(remaining_bytes, shared_memory_size);
       memcpy(shared_memory->memory(), current_ptr, chunk_size);
       sender_->Send(new StreamHostMsg_SyncAppendSharedMemory(
-          url, shared_memory->handle(), chunk_size));
+          url, shared_memory->handle(), static_cast<uint32_t>(chunk_size)));
       remaining_bytes -= chunk_size;
       current_ptr += chunk_size;
     }
@@ -300,7 +300,7 @@ void WebBlobRegistryImpl::BuilderImpl::SendOversizedDataForBlob(
     consolidation_.ReadMemory(consolidated_item_index, offset, chunk_size,
                               shared_memory->memory());
     sender_->Send(new BlobHostMsg_SyncAppendSharedMemory(
-        uuid_, shared_memory->handle(), chunk_size));
+        uuid_, shared_memory->handle(), static_cast<uint32_t>(chunk_size)));
     data_size -= chunk_size;
     offset += chunk_size;
   }