[wasm] Rework encoding of local declarations.

test/mjsunit/wasm/start-function.js

Index: test/mjsunit/wasm/start-function.js
diff --git a/test/mjsunit/wasm/start-function.js b/test/mjsunit/wasm/start-function.js
index 409857de345f7a307097b76f1417b7d6e5621dcf..5b39a06a74531aa1a6bb283b0cec6eda22a95888 100644
--- a/test/mjsunit/wasm/start-function.js
+++ b/test/mjsunit/wasm/start-function.js
@@ -23,8 +23,9 @@ function instantiate(sig, body) {
     kDeclFunctions, 1,
     0,                 // decl flags
     0, 0,              // signature
-    body.length, 0,    // body size
+    body.length + 1, 0,    // body size
   ]);
+  module = module.concat([kDeclNoLocals]);
   module = module.concat(body);
   module = module.concat([
     // -- declare start function
@@ -67,7 +68,7 @@ assertFails([2, kAstI32, kAstI32, kAstF32], [kExprGetLocal, 0]);
 assertFails([3, kAstI32, kAstI32, kAstF32, kAstF64], [kExprGetLocal, 0]);
 
 (function testInvalidIndex() {
-  var kBodySize = 1;
+  var kBodySize = 2;
   var data = bytesWithHeader(
     // -- signatures
     kDeclSignatures, 1,
@@ -76,6 +77,7 @@ assertFails([3, kAstI32, kAstI32, kAstF32, kAstF64], [kExprGetLocal, 0]);
     kDeclFunctions, 1,
     0,                 // decl flags
     0, 0,              // signature
+    kDeclNoLocals,
     kBodySize, 0,      // body size
     kExprNop,          // body
     // -- declare start function
@@ -88,7 +90,7 @@ assertFails([3, kAstI32, kAstI32, kAstF32, kAstF64], [kExprGetLocal, 0]);
 
 
 (function testTwoStartFuncs() {
-  var kBodySize = 1;
+  var kBodySize = 2;
   var data = bytesWithHeader(
     // -- signatures
     kDeclSignatures, 1,
@@ -98,6 +100,7 @@ assertFails([3, kAstI32, kAstI32, kAstF32, kAstF64], [kExprGetLocal, 0]);
     0,                 // decl flags
     0, 0,              // signature
     kBodySize, 0,      // body size
+    kDeclNoLocals,
     kExprNop,          // body
     // -- declare start function
     kDeclStartFunction,
@@ -112,7 +115,7 @@ assertFails([3, kAstI32, kAstI32, kAstF32, kAstF64], [kExprGetLocal, 0]);
 
 
 (function testRun() {
-  var kBodySize = 6;
+  var kBodySize = 7;
 
   var data = bytesWithHeader(
     kDeclMemory,
@@ -125,6 +128,7 @@ assertFails([3, kAstI32, kAstI32, kAstF32, kAstF64], [kExprGetLocal, 0]);
     0,                          // decl flags
     0, 0,                       // signature
     kBodySize, 0,               // code size
+    kDeclNoLocals,
     // -- start body
     kExprI32StoreMem, 0, kExprI8Const, 0, kExprI8Const, 77,
     // -- declare start function
@@ -139,8 +143,8 @@ assertFails([3, kAstI32, kAstI32, kAstF32, kAstF64], [kExprGetLocal, 0]);
 })();
 
 (function testStartFFI() {
-  var kBodySize = 2;
-  var kNameOffset = kHeaderSize + 4 + 9 + 7 + 3;
+  var kBodySize = 3;
+  var kNameOffset = kHeaderSize + 4 + 9 + 5 + kBodySize + 3;
 
   var data = bytesWithHeader(
     // -- signatures
@@ -155,6 +159,7 @@ assertFails([3, kAstI32, kAstI32, kAstF32, kAstF64], [kExprGetLocal, 0]);
     0,                          // decl flags
     0, 0,                       // signature
     kBodySize, 0,               // code size
+    kDeclNoLocals,
     // -- start body
     kExprCallFunction, 0,
     // -- declare start function