Port InspectorIndexedDBAgent to InspectorAgentState fields.

There's just one field for the enabled bit so this one's trivial.

For reference the PR that introduced the new
InspectorSessionState / InspectorAgentState / Fields
was https://chromium-review.googlesource.com/c/chromium/src/+/1149201.
We're migrating things from state_ to this new mechanism,
which allows incremental updates to flow back to the browser
process.

Bug: 851762
Change-Id: Ie709f8c99d196f5be018838e1cb9e70a2cb6aed8
Reviewed-on: https://chromium-review.googlesource.com/1159721
Commit-Queue: Johannes Henkel <johannes@chromium.org>
Reviewed-by: Andrey Kosyakov <caseq@chromium.org>
Reviewed-by: Chris Mumford <cmumford@chromium.org>
Cr-Commit-Position: refs/heads/master@{#580329}

third_party/blink/renderer/modules/indexeddb/inspector_indexed_db_agent.cc

@@ -90,11 +90,6 @@ typedef blink::protocol::IndexedDB::Backend::DeleteDatabaseCallback
     DeleteDatabaseCallback;
 
 namespace blink {
-
-namespace IndexedDBAgentState {
-static const char kIndexedDBAgentEnabled[] = "indexedDBAgentEnabled";
-};
-
 namespace {
 
 const char kIndexedDBObjectGroup[] = "indexeddb";
@@ -754,15 +749,15 @@ class DataLoader final : public ExecutableWithDatabase<RequestDataCallback> {
 InspectorIndexedDBAgent::InspectorIndexedDBAgent(
     InspectedFrames* inspected_frames,
     v8_inspector::V8InspectorSession* v8_session)
-    : inspected_frames_(inspected_frames), v8_session_(v8_session) {}
+    : inspected_frames_(inspected_frames),
+      v8_session_(v8_session),
+      enabled_(&agent_state_, /*default_value=*/false) {}
 
 InspectorIndexedDBAgent::~InspectorIndexedDBAgent() = default;
 
 void InspectorIndexedDBAgent::Restore() {
-  if (state_->booleanProperty(IndexedDBAgentState::kIndexedDBAgentEnabled,
-                              false)) {
+  if (enabled_.Get())
     enable();
-  }
 }
 
 void InspectorIndexedDBAgent::DidCommitLoadForLocalFrame(LocalFrame* frame) {
@@ -773,12 +768,12 @@ void InspectorIndexedDBAgent::DidCommitLoadForLocalFrame(LocalFrame* frame) {
 }
 
 Response InspectorIndexedDBAgent::enable() {
-  state_->setBoolean(IndexedDBAgentState::kIndexedDBAgentEnabled, true);
+  enabled_.Set(true);
   return Response::OK();
 }
 
 Response InspectorIndexedDBAgent::disable() {
-  state_->setBoolean(IndexedDBAgentState::kIndexedDBAgentEnabled, false);
+  enabled_.Clear();
   v8_session_->releaseObjectGroup(
       ToV8InspectorStringView(kIndexedDBObjectGroup));
   return Response::OK();

third_party/blink/renderer/modules/indexeddb/inspector_indexed_db_agent.h

@@ -86,6 +86,7 @@ class MODULES_EXPORT InspectorIndexedDBAgent final
  private:
   Member<InspectedFrames> inspected_frames_;
   v8_inspector::V8InspectorSession* v8_session_;
+  InspectorAgentState::Boolean enabled_;
 };
 
 }  // namespace blink