[wasm] memory size is an uint32_t, not a size_t.

src/wasm/wasm-module.h

 // Copyright 2015 the V8 project 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 V8_WASM_MODULE_H_
 #define V8_WASM_MODULE_H_
 
 #include "src/api.h"
 #include "src/handles.h"
 #include "src/wasm/wasm-opcodes.h"
@@ skipping 207 matching lines @@
   // -- Heap allocated --------------------------------------------------------
   Handle<JSObject> js_object;            // JavaScript module object.
   Handle<Context> context;               // JavaScript native context.
   Handle<JSArrayBuffer> mem_buffer;      // Handle to array buffer of memory.
   Handle<JSArrayBuffer> globals_buffer;  // Handle to array buffer of globals.
   Handle<FixedArray> function_table;     // indirect function table.
   std::vector<Handle<Code>> function_code;  // code objects for each function.
   std::vector<Handle<Code>> import_code;    // code objects for each import.
   // -- raw memory ------------------------------------------------------------
   byte* mem_start;  // start of linear memory.
-  size_t mem_size;  // size of the linear memory.
+  uint32_t mem_size;  // size of the linear memory.
   // -- raw globals -----------------------------------------------------------
   byte* globals_start;  // start of the globals area.
 
   explicit WasmModuleInstance(const WasmModule* m)
       : module(m),
         function_code(m->functions.size()),
         mem_start(nullptr),
         mem_size(0),
         globals_start(nullptr) {}
 };
@@ skipping 97 matching lines @@
 // secure. If it turns out that we need more complete checks, we could add a
 // special marker as internal field, which will definitely never occur anywhere
 // else.
 bool IsWasmObject(Handle<JSObject> object);
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_WASM_MODULE_H_