Harden yet more runtime functions

R=dslomov@chromium.org

Review URL: https://codereview.chromium.org/270273005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21197 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/debug.cc

@@ -1108,7 +1108,7 @@ Handle<DebugInfo> Debug::GetDebugInfo(Handle<SharedFunctionInfo> shared) {
 }
 
 
-void Debug::SetBreakPoint(Handle<JSFunction> function,
+bool Debug::SetBreakPoint(Handle<JSFunction> function,
                           Handle<Object> break_point_object,
                           int* source_position) {
   HandleScope scope(isolate_);
@@ -1119,7 +1119,7 @@ void Debug::SetBreakPoint(Handle<JSFunction> function,
   Handle<SharedFunctionInfo> shared(function->shared());
   if (!EnsureDebugInfo(shared, function)) {
     // Return if retrieving debug info failed.
-    return;
+    return true;
   }
 
   Handle<DebugInfo> debug_info = GetDebugInfo(shared);
@@ -1134,7 +1134,7 @@ void Debug::SetBreakPoint(Handle<JSFunction> function,
   *source_position = it.position();
 
   // At least one active break point now.
-  ASSERT(debug_info->GetBreakPointCount() > 0);
+  return debug_info->GetBreakPointCount() > 0;
 }
 
 

src/debug.h

@@ -219,7 +219,7 @@ class Debug {
   void PreemptionWhileInDebugger();
 
   Object* Break(Arguments args);
-  void SetBreakPoint(Handle<JSFunction> function,
+  bool SetBreakPoint(Handle<JSFunction> function,
                      Handle<Object> break_point_object,
                      int* source_position);
   bool SetBreakPointForScript(Handle<Script> script,

src/liveedit.h

@@ -278,9 +278,13 @@ class FunctionInfoWrapper : public JSArrayBasedStruct<FunctionInfoWrapper> {
 class SharedInfoWrapper : public JSArrayBasedStruct<SharedInfoWrapper> {
  public:
   static bool IsInstance(Handle<JSArray> array) {
-    return array->length() == Smi::FromInt(kSize_) &&
-        Object::GetElement(array->GetIsolate(), array, kSharedInfoOffset_)
-            .ToHandleChecked()->IsJSValue();
+    if (array->length() != Smi::FromInt(kSize_)) return false;
+    Handle<Object> element(
+        Object::GetElement(array->GetIsolate(),
+                           array,
+                           kSharedInfoOffset_).ToHandleChecked());
+    if (!element->IsJSValue()) return false;
+    return Handle<JSValue>::cast(element)->value()->IsSharedFunctionInfo();
   }
 
   explicit SharedInfoWrapper(Handle<JSArray> array)