Revert of [debugger] simplify fetching scripts for inspector. (patchset #6...

Revert of [debugger] simplify fetching scripts for inspector. (patchset #6 id:100001 of https://codereview.chromium.org/2465833002/ )

Reason for revert:
https://build.chromium.org/p/client.v8.fyi/builders/V8-Blink%20Linux%2064/builds/11118

Rule of thumb: As long as the tests have not migrated yet, you most certainly need a blink rebase whenever you change expectations.

Original issue's description:
> [debugger] simplify fetching scripts for inspector.
>
> The old code path is going to be removed with the debug context api.
>
> R=kozyatinskiy@chromium.org

TBR=kozyatinskiy@chromium.org,yangguo@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review-Url: https://codereview.chromium.org/2473273005
Cr-Commit-Position: refs/heads/master@{#40764}

src/api.cc

@@ -8949,18 +8949,13 @@ void DebugInterface::GetLoadedScripts(
     PersistentValueVector<DebugInterface::Script>& scripts) {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(v8_isolate);
   ENTER_V8(isolate);
-  {
-    i::DisallowHeapAllocation no_gc;
-    i::Script::Iterator iterator(isolate);
-    i::Script* script;
-    while ((script = iterator.Next())) {
-      if (script->type() != i::Script::TYPE_NORMAL) continue;
-      if (script->HasValidSource()) {
   i::HandleScope handle_scope(isolate);
-        i::Handle<i::Script> script_handle(script, isolate);
-        scripts.Append(ToApiHandle<Script>(script_handle));
-      }
-    }
+  i::Handle<i::FixedArray> instances = isolate->debug()->GetLoadedScripts();
+  for (int i = 0; i < instances->length(); i++) {
+    i::Handle<i::Script> script =
+        i::Handle<i::Script>(i::Script::cast(instances->get(i)));
+    if (script->type() != i::Script::TYPE_NORMAL) continue;
+    scripts.Append(ToApiHandle<Script>(script));
   }
 }
 

test/inspector/debugger/script-on-after-compile-expected.txt

@@ -661,4 +661,4 @@ scriptParsed
     startLine : 0
     url : 
 }
-Remove script references and re-enable debugger.
+Run gc and then Debugger.enable()..

test/inspector/debugger/script-on-after-compile.js

 // 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.
+// Flags: --expose_gc
 
 print("Checks that inspector correctly process compiled scripts");
 
@@ -48,10 +49,9 @@ addScripts()
   .then(() => Protocol.Debugger.enable())
   .then(addScripts)
   .then(() => Protocol.Debugger.disable())
-  .then(() => InspectorTest.log("Remove script references and re-enable debugger."))
-  .then(() => Protocol.Runtime.evaluate(
-      { expression: "for (let i = 1; i < 20; ++i) eval(`foo${i} = undefined`);" }))
-  .then(() => Protocol.HeapProfiler.collectGarbage())
+
+  .then(() => InspectorTest.log("Run gc and then Debugger.enable().."))
+  .then(() => Protocol.Runtime.evaluate({ expression: "for (let i = 1; i < 20; ++i) eval(`foo${i} = undefined`); gc();" }))
   .then(() => Protocol.Debugger.enable())
   .then(InspectorTest.completeTest);