Revert of Allow a ParseInfo without a script for %SetCode users

src/source-position.cc

 // Copyright 2016 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.
 
 #include "src/source-position.h"
 #include "src/compilation-info.h"
 #include "src/objects-inl.h"
 
 namespace v8 {
 namespace internal {
 
 std::ostream& operator<<(std::ostream& out, const SourcePositionInfo& pos) {
   Handle<SharedFunctionInfo> function(pos.function);
-  String* name = nullptr;
-  if (function->script()->IsScript()) {
-    Script* script = Script::cast(function->script());
-    if (script->name()->IsString()) {
-      name = String::cast(script->name());
-    }
-  }
+  Handle<Script> script(Script::cast(function->script()));
   out << "<";
-  if (name != nullptr) {
-    out << name->ToCString(DISALLOW_NULLS).get();
+  if (script->name()->IsString()) {
+    out << String::cast(script->name())->ToCString(DISALLOW_NULLS).get();
   } else {
     out << "unknown";
   }
   out << ":" << pos.line + 1 << ":" << pos.column + 1 << ">";
   return out;
 }
 
 std::ostream& operator<<(std::ostream& out,
                          const std::vector<SourcePositionInfo>& stack) {
   bool first = true;
@@ skipping 43 matching lines @@
     pos = inl.position;
   }
   Handle<SharedFunctionInfo> function(
       SharedFunctionInfo::cast(deopt_data->SharedFunctionInfo()));
   stack.push_back(SourcePositionInfo(pos, function));
   return stack;
 }
 
 void SourcePosition::Print(std::ostream& out,
                            SharedFunctionInfo* function) const {
+  Script* script = Script::cast(function->script());
+  Object* source_name = script->name();
   Script::PositionInfo pos;
-  Object* source_name = nullptr;
-  if (function->script()->IsScript()) {
-    Script* script = Script::cast(function->script());
-    source_name = script->name();
-    script->GetPositionInfo(ScriptOffset(), &pos, Script::WITH_OFFSET);
-  }
+  script->GetPositionInfo(ScriptOffset(), &pos, Script::WITH_OFFSET);
   out << "<";
-  if (source_name != nullptr && source_name->IsString()) {
+  if (source_name->IsString()) {
     out << String::cast(source_name)
                ->ToCString(DISALLOW_NULLS, ROBUST_STRING_TRAVERSAL)
                .get();
   } else {
     out << "unknown";
   }
   out << ":" << pos.line + 1 << ":" << pos.column + 1 << ">";
 }
 
 void SourcePosition::Print(std::ostream& out, Code* code) const {
@@ skipping 13 matching lines @@
       Print(out, function);
     }
     out << " inlined at ";
     inl.position.Print(out, code);
   }
 }
 
 SourcePositionInfo::SourcePositionInfo(SourcePosition pos,
                                        Handle<SharedFunctionInfo> f)
     : position(pos), function(f) {
-  if (function->script()->IsScript()) {
-    Handle<Script> script(Script::cast(function->script()));
-    Script::PositionInfo info;
-    if (Script::GetPositionInfo(script, pos.ScriptOffset(), &info,
-                                Script::WITH_OFFSET)) {
-      line = info.line;
-      column = info.column;
-    }
+  Handle<Script> script(Script::cast(function->script()));
+  Script::PositionInfo info;
+  if (Script::GetPositionInfo(script, pos.ScriptOffset(), &info,
+                              Script::WITH_OFFSET)) {
+    line = info.line;
+    column = info.column;
   }
 }
 
 }  // namespace internal
 }  // namespace v8