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

src/source-position.cc

Index: src/source-position.cc
diff --git a/src/source-position.cc b/src/source-position.cc
index 02bb339357f3269e4cf65b57ee577e0a94c72838..ff204be73d327b2821646b77019badcff563d78d 100644
--- a/src/source-position.cc
+++ b/src/source-position.cc
@@ -11,16 +11,10 @@
 
 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";
   }
@@ -84,15 +78,12 @@
 
 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();
@@ -126,14 +117,12 @@
 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;
   }
 }