Fix harmony sloppy block scoping dynamic redeclaration check

The previous code did not properly check for harmony const when
doing the dynamic redeclaration check. This was masked in the
test because each eval had an initializer, and the initializer was what
triggered the exception.

This patch tightens the test by removing initializers and fixes the bug in
DeclareLookupSlot.

Also change the test to use assertThrows where possible.

BUG=v8:4550
LOG=n

Review URL: https://codereview.chromium.org/1437003006

Cr-Commit-Position: refs/heads/master@{#31995}

src/runtime/runtime-scopes.cc

@@ -231,7 +231,8 @@ Object* DeclareLookupSlot(Isolate* isolate, Handle<String> name,
                         &binding_flags);
     if (attributes != ABSENT &&
         (binding_flags == MUTABLE_CHECK_INITIALIZED ||
-         binding_flags == IMMUTABLE_CHECK_INITIALIZED)) {
+         binding_flags == IMMUTABLE_CHECK_INITIALIZED ||
+         binding_flags == IMMUTABLE_CHECK_INITIALIZED_HARMONY)) {
       return ThrowRedeclarationError(isolate, name);
     }
     attr = static_cast<PropertyAttributes>(attr & ~EVAL_DECLARED);

test/mjsunit/harmony/block-eval-var-over-legacy-const.js

@@ -6,61 +6,36 @@
 
 // Var-let conflict in a function throws, even if the var is in an eval
 
-let caught = false;
-
 // Throws at the top level of a function
-try {
-  (function() {
+assertThrows(function() {
   let x = 1;
   eval('const x = 2');
-  })()
-} catch (e) {
-  caught = true;
-}
-assertTrue(caught);
+}, TypeError);
 
 // If the eval is in its own block scope, throws
-caught = false;
-try {
-  (function() {
+assertThrows(function() {
   let y = 1;
   { eval('const y = 2'); }
-  })()
-} catch (e) {
-  caught = true;
-}
-assertTrue(caught);
+}, TypeError);
 
 // If the let is in its own block scope, with the eval, throws
-caught = false
-try {
-  (function() {
+assertThrows(function() {
   {
     let x = 1;
     eval('const x = 2');
   }
-  })();
-} catch (e) {
-  caught = true;
-}
-assertTrue(caught);
+}, TypeError);
 
 // Legal if the let is no longer visible
-caught = false
-try {
-  (function() {
+assertDoesNotThrow(function() {
   {
     let x = 1;
   }
   eval('const x = 2');
-  })();
-} catch (e) {
-  caught = true;
-}
-assertFalse(caught);
+});
 
 // In global scope
-caught = false;
+let caught = false;
 try {
   let z = 1;
   eval('const z = 2');

test/mjsunit/harmony/block-eval-var-over-let.js

@@ -6,116 +6,68 @@
 
 // Var-let conflict in a function throws, even if the var is in an eval
 
-let caught = false;
-
 // Throws at the top level of a function
-try {
-  (function() {
+assertThrows(function() {
   let x = 1;
-    eval('var x = 2');
-  })()
-} catch (e) {
-  caught = true;
-}
-assertTrue(caught);
+  eval('var x');
+}, TypeError);
 
 // If the eval is in its own block scope, throws
-caught = false;
-try {
-  (function() {
+assertThrows(function() {
   let y = 1;
-    { eval('var y = 2'); }
-  })()
-} catch (e) {
-  caught = true;
-}
-assertTrue(caught);
+  { eval('var y'); }
+}, TypeError);
 
 // If the let is in its own block scope, with the eval, throws
-caught = false
-try {
-  (function() {
+assertThrows(function() {
   {
     let x = 1;
-      eval('var x = 2');
+    eval('var x');
   }
-  })();
-} catch (e) {
-  caught = true;
-}
-assertTrue(caught);
+}, TypeError);
 
 // Legal if the let is no longer visible
-caught = false
-try {
-  (function() {
+assertDoesNotThrow(function() {
   {
     let x = 1;
   }
-    eval('var x = 2');
-  })();
-} catch (e) {
-  caught = true;
-}
-assertFalse(caught);
+  eval('var x');
+});
 
 // All the same works for const:
 // Throws at the top level of a function
-try {
-  (function() {
+assertThrows(function() {
   const x = 1;
-    eval('var x = 2');
-  })();
-} catch (e) {
-  caught = true;
-}
-assertTrue(caught);
+  eval('var x');
+}, TypeError);
 
 // If the eval is in its own block scope, throws
-caught = false;
-try {
-  (function() {
+assertThrows(function() {
   const y = 1;
-    { eval('var y = 2'); }
-  })();
-} catch (e) {
-  caught = true;
-}
-assertTrue(caught);
+  { eval('var y'); }
+}, TypeError);
 
 // If the const is in its own block scope, with the eval, throws
-caught = false
-try {
-  (function() {
+assertThrows(function() {
   {
     const x = 1;
-      eval('var x = 2');
+    eval('var x');
   }
-  })();
-} catch (e) {
-  caught = true;
-}
-assertTrue(caught);
+}, TypeError);
 
 // Legal if the const is no longer visible
-caught = false
-try {
-  (function() {
+assertDoesNotThrow(function() {
   {
     const x = 1;
   }
-    eval('var x = 2');
-  })();
-} catch (e) {
-  caught = true;
-}
-assertFalse(caught);
+  eval('var x');
+});
 
 // In global scope
-caught = false;
+let caught = false;
 try {
   let z = 1;
-  eval('var z = 2');
+  eval('var z');
 } catch (e) {
   caught = true;
 }
@@ -138,7 +90,7 @@ caught = false;
 try {
   (function() {
     with ({x: 1}) {
-      eval("var x = 2;");
+      eval("var x");
     }
   })();
 } catch (e) {
@@ -152,7 +104,7 @@ try {
   (function() {
     let x;
     with ({x: 1}) {
-      eval("var x = 2;");
+      eval("var x");
     }
   })();
 } catch (e) {