Revert "Use a Persistent FileChooserClient to avoid GC"

This reverts commit fee1e3c8.

Reason for revert: Suspected of causing memory leak in various tests (http://crbug.com/972005) e.g., crbgug.
* fast/forms/file/file-input-click.html
* fast/forms/file/file-input-key-enter.html
...


Original change's description:
> Use a Persistent FileChooserClient to avoid GC
> 
> Previous to this change, the FileChooserClient was only held by
> a WeakPersistent pointer, and as a result, the client could get
> garbage collected. This led to user-visible bugs, such as
> crbug.com/844119. This is now corrected.
> 
> Bug: 844119
> Change-Id: I7ab788e85dba4d6343a3abceafb092ef1cfe64f9
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1639046
> Commit-Queue: Kent Tamura <tkent@chromium.org>
> Reviewed-by: Kent Tamura <tkent@chromium.org>
> Auto-Submit: Mason Freed <masonfreed@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#666970}

TBR=tkent@chromium.org,masonfreed@chromium.org

Change-Id: Ief378adea1a4e19cf3fe0fe0a4b2517edeb8529f
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 844119
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1650020Reviewed-by: Samuel Huang <huangs@chromium.org>
Commit-Queue: Samuel Huang <huangs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#667124}

third_party/blink/renderer/core/BUILD.gn

@@ -1868,7 +1868,6 @@ jumbo_source_set("unit_tests") {
     "html/custom/custom_element_upgrade_sorter_test.cc",
     "html/forms/email_input_type_test.cc",
     "html/forms/external_popup_menu_test.cc",
-    "html/forms/file_chooser_test.cc",
     "html/forms/file_input_type_test.cc",
     "html/forms/form_controller_test.cc",
     "html/forms/form_data_test.cc",

third_party/blink/renderer/core/html/forms/file_chooser.h

@@ -96,7 +96,7 @@ class FileChooser : public RefCounted<FileChooser> {
   // mojom::blink::FileChooser callback
   void DidChooseFiles(mojom::blink::FileChooserResultPtr result);
 
-  Persistent<FileChooserClient> client_;
+  WeakPersistent<FileChooserClient> client_;
   mojom::blink::FileChooserParamsPtr params_;
   Persistent<ChromeClientImpl> chrome_client_impl_;
   mojom::blink::FileChooserPtr file_chooser_;

third_party/blink/renderer/core/html/forms/file_chooser_test.cc

-// Copyright 2019 The Chromium 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 "third_party/blink/renderer/core/html/forms/file_chooser.h"
-#include "testing/gtest/include/gtest/gtest.h"
-#include "third_party/blink/renderer/core/frame/frame_test_helpers.h"
-#include "third_party/blink/renderer/core/frame/web_local_frame_impl.h"
-#include "third_party/blink/renderer/core/html/forms/mock_file_chooser.h"
-#include "third_party/blink/renderer/core/page/chrome_client_impl.h"
-
-namespace blink {
-
-class FileChooserTest : public testing::Test {
- protected:
-  void SetUp() override { web_view_ = helper_.Initialize(); }
-
-  frame_test_helpers::WebViewHelper helper_;
-  WebViewImpl* web_view_;
-};
-
-TEST_F(FileChooserTest, NotGarbageCollected) {
-  LocalFrame* frame = helper_.LocalMainFrame()->GetFrame();
-  auto* client = MakeGarbageCollected<MockFileChooserClient>(frame);
-  mojom::blink::FileChooserParams params;
-  params.title = g_empty_string;
-  scoped_refptr<FileChooser> chooser = FileChooser::Create(client, params);
-  ThreadState::Current()->CollectAllGarbageForTesting();
-  // This tests the nullness of FileChooser::client_.
-  EXPECT_TRUE(chooser->FrameOrNull());
-}
-
-}  // namespace blink

third_party/blink/renderer/core/html/forms/mock_file_chooser.h

@@ -74,28 +74,5 @@ class MockFileChooser : public mojom::blink::FileChooser {
   base::OnceClosure reached_callback_;
 };
 
-// A FileChooserClient which makes FileChooser::OpenFileChooser() success.
-class MockFileChooserClient
-    : public GarbageCollectedFinalized<MockFileChooserClient>,
-      public FileChooserClient {
-  USING_GARBAGE_COLLECTED_MIXIN(MockFileChooserClient);
-
- public:
-  explicit MockFileChooserClient(LocalFrame* frame) : frame_(frame) {}
-  void Trace(Visitor* visitor) override {
-    visitor->Trace(frame_);
-    FileChooserClient::Trace(visitor);
-  }
-
- private:
-  // FilesChosen() and WillOpenPopup() are never called in the test.
-  void FilesChosen(FileChooserFileInfoList, const base::FilePath&) override {}
-  void WillOpenPopup() override {}
-
-  LocalFrame* FrameOrNull() const override { return frame_; }
-
-  Member<LocalFrame> frame_;
-};
-
 }  // namespace blink
 #endif  // THIRD_PARTY_BLINK_RENDERER_CORE_HTML_FORMS_MOCK_FILE_CHOOSER_H_

third_party/blink/renderer/core/page/chrome_client_impl_test.cc

@@ -230,6 +230,29 @@ TEST_F(PagePopupSuppressionTest, SuppressDateTimeChooser) {
   EXPECT_TRUE(CanOpenDateTimeChooser());
 }
 
+// A FileChooserClient which makes FileChooser::OpenFileChooser() success.
+class MockFileChooserClient
+    : public GarbageCollectedFinalized<MockFileChooserClient>,
+      public FileChooserClient {
+  USING_GARBAGE_COLLECTED_MIXIN(MockFileChooserClient);
+
+ public:
+  explicit MockFileChooserClient(LocalFrame* frame) : frame_(frame) {}
+  void Trace(Visitor* visitor) override {
+    visitor->Trace(frame_);
+    FileChooserClient::Trace(visitor);
+  }
+
+ private:
+  // FilesChosen() and WillOpenPopup() are never called in the test.
+  void FilesChosen(FileChooserFileInfoList, const base::FilePath&) override {}
+  void WillOpenPopup() override {}
+
+  LocalFrame* FrameOrNull() const override { return frame_; }
+
+  Member<LocalFrame> frame_;
+};
+
 class FileChooserQueueTest : public testing::Test {
  protected:
   void SetUp() override {