refactor BlockVisitor in asm to wasm and fix tests

test/mjsunit/wasm/asm-wasm.js

 // 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.
 
 // Flags: --expose-wasm
 
 function EmptyTest() {
   "use asm";
   function caller() {
     empty();
     return 11;
   }
   function empty() {
   }
   return {caller: caller};
 }
 
-assertEquals(11, WASM.asmCompileRun(EmptyTest.toString()));
+assertEquals(11, _WASMEXP_.asmCompileRun(EmptyTest.toString()));
 
 function IntTest() {
   "use asm";
   function sum(a, b) {
     a = a|0;
     b = b|0;
     var c = (b + 1)|0
     var d = 3.0;
     var e = d | 0;  // double conversion
     return (a + c + 1)|0;
@@ skipping 647 matching lines @@
   "use asm"
 
   function caller() {
     var x = 1;
     return ((x > 0) ? 41 : 71)|0;
   }
 
   return {caller:caller};
 }
 
-assertEquals(41, WASM.asmCompileRun(TestConditional.toString()));
+assertEquals(41, _WASMEXP_.asmCompileRun(TestConditional.toString()));
 
 function TestSwitch() {
   "use asm"
 
   function caller() {
     var ret = 0;
     var x = 7;
     switch (x) {
       case 1: return 0;
       case 7: {
         ret = 12;
         break;
       }
       default: return 0;
     }
     switch (x) {
       case 1: return 0;
       case 8: return 0;
       default: ret = (ret + 11)|0;
     }
     return ret|0;
   }
 
   return {caller:caller};
 }
 
-assertEquals(23, WASM.asmCompileRun(TestSwitch.toString()));
+assertEquals(23, _WASMEXP_.asmCompileRun(TestSwitch.toString()));
 
 function TestSwitchFallthrough() {
   "use asm"
 
   function caller() {
     var x = 17;
     var ret = 0;
     switch (x) {
       case 17:
       case 14: ret = 39;
       case 1: ret = (ret + 3)|0;
       case 4: break;
       default: ret = (ret + 1)|0;
     }
     return ret|0;
   }
 
   return {caller:caller};
 }
 
-assertEquals(42, WASM.asmCompileRun(TestSwitchFallthrough.toString()));
+assertEquals(42, _WASMEXP_.asmCompileRun(TestSwitchFallthrough.toString()));
 
 function TestNestedSwitch() {
   "use asm"
 
   function caller() {
     var x = 3;
     var y = -13;
     switch (x) {
       case 1: return 0;
       case 3: {
         switch (y) {
           case 2: return 0;
           case -13: return 43;
           default: return 0;
         }
       }
       default: return 0;
     }
     return 0;
   }
 
   return {caller:caller};
 }
 
-assertEquals(43, WASM.asmCompileRun(TestNestedSwitch.toString()));
+assertEquals(43, _WASMEXP_.asmCompileRun(TestNestedSwitch.toString()));