[wasm] Enable sign extension opcodes by default

Change-Id: Id6f87f55541eba44a22be2721f9182095ca69359
Reviewed-on: https://chromium-review.googlesource.com/1085508Reviewed-by: Ben Smith <binji@chromium.org>
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53501}

src/flag-definitions.h

@@ -587,7 +587,7 @@ DEFINE_BOOL(experimental_wasm_threads, false,
             "enable prototype threads for wasm")
 DEFINE_BOOL(experimental_wasm_sat_f2i_conversions, false,
             "enable non-trapping float-to-int conversions for wasm")
-DEFINE_BOOL(experimental_wasm_se, false,
+DEFINE_BOOL(experimental_wasm_se, true,
             "enable prototype sign extension opcodes for wasm")
 DEFINE_BOOL(experimental_wasm_anyref, false,
             "enable prototype anyref support for wasm")

test/cctest/wasm/test-run-wasm.cc

@@ -1962,9 +1962,6 @@ static void TestBuildGraphForSimpleExpression(WasmOpcode opcode) {
   Isolate* isolate = CcTest::InitIsolateOnce();
   Zone zone(isolate->allocator(), ZONE_NAME);
   HandleScope scope(isolate);
-  // TODO(gdeepti): Enable this test for sign extension opcodes when lowering
-  // is enabled.
-  if (WasmOpcodes::IsSignExtensionOpcode(opcode)) return;
   // TODO(ahaas): Enable this test for anyref opcodes when code generation for
   // them is implemented.
   if (WasmOpcodes::IsAnyRefOpcode(opcode)) return;