[wasm] Change the constant kV8MaxWasmMemoryPages to a command line flag.

src/wasm/module-decoder.cc

Index: src/wasm/module-decoder.cc
diff --git a/src/wasm/module-decoder.cc b/src/wasm/module-decoder.cc
index d7c7954de2e5d700121aad968d676e193d21d163..c5c39a1cd97b305c82b77bca88859e8ba72d5a59 100644
--- a/src/wasm/module-decoder.cc
+++ b/src/wasm/module-decoder.cc
@@ -320,10 +320,11 @@ class ModuleDecoder : public Decoder {
           case kExternalMemory: {
             // ===== Imported memory =========================================
             bool has_max = false;
-            consume_resizable_limits("memory", "pages", kV8MaxWasmMemoryPages,
-                                     &module->min_mem_pages, &has_max,
-                                     kSpecMaxWasmMemoryPages,
-                                     &module->max_mem_pages);
+            consume_resizable_limits(
+                "memory", "pages",
+                static_cast<uint32_t>(FLAG_wasm_max_mem_pages),
+                &module->min_mem_pages, &has_max, kSpecMaxWasmMemoryPages,
+                &module->max_mem_pages);
             SetHasMemory(module);
             break;
           }
@@ -396,8 +397,9 @@ class ModuleDecoder : public Decoder {
       for (uint32_t i = 0; ok() && i < memory_count; i++) {
         bool has_max = false;
         consume_resizable_limits(
-            "memory", "pages", kV8MaxWasmMemoryPages, &module->min_mem_pages,
-            &has_max, kSpecMaxWasmMemoryPages, &module->max_mem_pages);
+            "memory", "pages", static_cast<uint32_t>(FLAG_wasm_max_mem_pages),
+            &module->min_mem_pages, &has_max, kSpecMaxWasmMemoryPages,
+            &module->max_mem_pages);
       }
       SetHasMemory(module);
       section_iter.advance();