Fix the flaky Mojo connection of ContentSettingsManager

The reason for the flaky Mojo connection of ContentSettingsManager
was that |content_settings_manager_| tried to connect to its
receiver via BrowserInterfaceBroker in ContentSettingsAgentImpl
ctor once, but BrowserInterfaceBroker could be reset before
|content_settings_manager_| was connected.
This CL ensures its connection to retry in DidCommitProvisionalLoad
if it is not connected.

Bug: 936482
Change-Id: I29db1ea13e2fa4de49f431d07ac249ed6e318d1d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1897576Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Oksana Zhuravlova <oksamyt@chromium.org>
Commit-Queue: Miyoung Shin <myid.shin@igalia.com>
Cr-Commit-Position: refs/heads/master@{#713626}

chrome/renderer/content_settings_agent_impl.cc

@@ -125,9 +125,7 @@ ContentSettingsAgentImpl::ContentSettingsAgentImpl(
   render_frame->GetAssociatedInterfaceRegistry()->AddInterface(
       base::Bind(&ContentSettingsAgentImpl::OnContentSettingsAgentRequest,
                  base::Unretained(this)));
-
-  render_frame->GetBrowserInterfaceBroker()->GetInterface(
-      content_settings_manager_.BindNewPipeAndPassReceiver());
+  EnsureContentSettingsManagerConnection();
 
   content::RenderFrame* main_frame =
       render_frame->GetRenderView()->GetMainRenderFrame();
@@ -147,6 +145,16 @@ ContentSettingsAgentImpl::ContentSettingsAgentImpl(
 
 ContentSettingsAgentImpl::~ContentSettingsAgentImpl() {}
 
+void ContentSettingsAgentImpl::EnsureContentSettingsManagerConnection() {
+  if (content_settings_manager_.is_bound() &&
+      content_settings_manager_.is_connected())
+    return;
+
+  content_settings_manager_.reset();
+  render_frame()->GetBrowserInterfaceBroker()->GetInterface(
+      content_settings_manager_.BindNewPipeAndPassReceiver());
+}
+
 #if BUILDFLAG(ENABLE_EXTENSIONS)
 void ContentSettingsAgentImpl::SetExtensionDispatcher(
     extensions::Dispatcher* extension_dispatcher) {
@@ -204,6 +212,8 @@ void ContentSettingsAgentImpl::DidCommitProvisionalLoad(
   if (frame->Parent())
     return;  // Not a top-level navigation.
 
+  EnsureContentSettingsManagerConnection();
+
   if (!is_same_document_navigation) {
     // Clear "block" flags for the new page. This needs to happen before any of
     // |allowScript()|, |allowScriptFromSource()|, |allowImage()|, or

chrome/renderer/content_settings_agent_impl.h

@@ -165,6 +165,9 @@ class ContentSettingsAgentImpl
   bool AllowStorageAccess(
       chrome::mojom::ContentSettingsManager::StorageType storage_type);
 
+  // Ensures that |content_settings_manager_| is connected.
+  void EnsureContentSettingsManagerConnection();
+
   mojo::Remote<chrome::mojom::ContentSettingsManager> content_settings_manager_;
 
 #if BUILDFLAG(ENABLE_EXTENSIONS)