From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: deepak1556 <hop2deep@gmail.com>
Date: Mon, 18 May 2020 11:12:26 -0700
Subject: allow disabling blink scheduler throttling per RenderView

This allows us to disable throttling for hidden windows.

diff --git a/content/browser/renderer_host/render_view_host_impl.cc b/content/browser/renderer_host/render_view_host_impl.cc
index 1f6d9be10432416f591a616805494b5d78975df1..e73f70c62ac2e69c918bdf39bd53f74a47066f4e 100644
--- a/content/browser/renderer_host/render_view_host_impl.cc
+++ b/content/browser/renderer_host/render_view_host_impl.cc
@@ -665,6 +665,11 @@ void RenderViewHostImpl::SetBackgroundOpaque(bool opaque) {
   GetWidget()->GetAssociatedFrameWidget()->SetBackgroundOpaque(opaque);
 }
 
+void RenderViewHostImpl::SetSchedulerThrottling(bool allowed) {
+  if (auto& broadcast = GetAssociatedPageBroadcast())
+    broadcast->SetSchedulerThrottling(allowed);
+}
+
 bool RenderViewHostImpl::IsMainFrameActive() {
   return is_active();
 }
diff --git a/content/browser/renderer_host/render_view_host_impl.h b/content/browser/renderer_host/render_view_host_impl.h
index 3ccc771a82992ae70c770fa6d2dde92904aa17db..505091e9006f7d41fa8d02e603afef1d10b35bf4 100644
--- a/content/browser/renderer_host/render_view_host_impl.h
+++ b/content/browser/renderer_host/render_view_host_impl.h
@@ -138,6 +138,7 @@ class CONTENT_EXPORT RenderViewHostImpl
   void EnablePreferredSizeMode() override;
   void WriteIntoTrace(perfetto::TracedProto<TraceProto> context) const override;
 
+  void SetSchedulerThrottling(bool allowed) override;
   void SendWebPreferencesToRenderer();
   void SendRendererPreferencesToRenderer(
       const blink::RendererPreferences& preferences);
diff --git a/content/public/browser/render_view_host.h b/content/public/browser/render_view_host.h
index 4d2a4c6746e1dbfc619faf2e16eaa4948d74e372..6c9f190ff595234eca18ff20ca0655da4689b7a2 100644
--- a/content/public/browser/render_view_host.h
+++ b/content/public/browser/render_view_host.h
@@ -77,6 +77,9 @@ class CONTENT_EXPORT RenderViewHost {
   virtual void WriteIntoTrace(
       perfetto::TracedProto<TraceProto> context) const = 0;
 
+  // Disable/Enable scheduler throttling.
+  virtual void SetSchedulerThrottling(bool allowed) = 0;
+
  private:
   // This interface should only be implemented inside content.
   friend class RenderViewHostImpl;
diff --git a/content/renderer/render_view_impl.h b/content/renderer/render_view_impl.h
index 99978b33c294ebe37192baccb29f0a34a25aed17..ef6e9ae24979538b8746aca898d1f302827491d8 100644
--- a/content/renderer/render_view_impl.h
+++ b/content/renderer/render_view_impl.h
@@ -151,6 +151,8 @@ class CONTENT_EXPORT RenderViewImpl : public blink::WebViewClient,
   static WindowOpenDisposition NavigationPolicyToDisposition(
       blink::WebNavigationPolicy policy);
 
+  void OnSetSchedulerThrottling(bool allowed);
+
   // ---------------------------------------------------------------------------
   // ADDING NEW FUNCTIONS? Please keep private functions alphabetized and put
   // it in the same order in the .cc file as it was in the header.
diff --git a/third_party/blink/public/mojom/page/page.mojom b/third_party/blink/public/mojom/page/page.mojom
index 39bfc2200e924d0c589cfd07f085f182ef6853a6..bddff6d5ad3f6d08c4dc48e66ebc5319b1a5ec28 100644
--- a/third_party/blink/public/mojom/page/page.mojom
+++ b/third_party/blink/public/mojom/page/page.mojom
@@ -108,4 +108,7 @@ interface PageBroadcast {
 
   // Sent to whole page, but should only be used by the main frame.
   SetPageBaseBackgroundColor(skia.mojom.SkColor? color);
+
+  // Whether to enable the Renderer scheduler background throttling.
+  SetSchedulerThrottling(bool allowed);
 };
diff --git a/third_party/blink/public/web/web_view.h b/third_party/blink/public/web/web_view.h
index 5e4032ccf916f969cd669af7d983becddb57c72b..a858c9f2fa609ae756a2e70d0362f2de372dd5be 100644
--- a/third_party/blink/public/web/web_view.h
+++ b/third_party/blink/public/web/web_view.h
@@ -364,6 +364,7 @@ class WebView {
   // Scheduling -----------------------------------------------------------
 
   virtual PageScheduler* Scheduler() const = 0;
+  virtual void SetSchedulerThrottling(bool allowed) = 0;
 
   // Visibility -----------------------------------------------------------
 
diff --git a/third_party/blink/renderer/core/exported/web_view_impl.cc b/third_party/blink/renderer/core/exported/web_view_impl.cc
index 3f6460ceee1e3268db45fec668a5e75353643bcb..818394c235c3f71289218098c7db77e00d156d92 100644
--- a/third_party/blink/renderer/core/exported/web_view_impl.cc
+++ b/third_party/blink/renderer/core/exported/web_view_impl.cc
@@ -3727,6 +3727,13 @@ PageScheduler* WebViewImpl::Scheduler() const {
   return GetPage()->GetPageScheduler();
 }
 
+void WebViewImpl::SetSchedulerThrottling(bool allowed) {
+  DCHECK(GetPage());
+  scheduler_throttling_allowed_ = allowed;
+  GetPage()->GetPageScheduler()->SetPageVisible(allowed ?
+      (GetVisibilityState() == mojom::blink::PageVisibilityState::kVisible) : true);
+}
+
 void WebViewImpl::SetVisibilityState(
     mojom::blink::PageVisibilityState visibility_state,
     bool is_initial_state) {
@@ -3738,7 +3745,8 @@ void WebViewImpl::SetVisibilityState(
   }
   GetPage()->SetVisibilityState(visibility_state, is_initial_state);
   GetPage()->GetPageScheduler()->SetPageVisible(
-      visibility_state == mojom::blink::PageVisibilityState::kVisible);
+      scheduler_throttling_allowed_ ?
+          (visibility_state == mojom::blink::PageVisibilityState::kVisible) : true);
 }
 
 mojom::blink::PageVisibilityState WebViewImpl::GetVisibilityState() {
diff --git a/third_party/blink/renderer/core/exported/web_view_impl.h b/third_party/blink/renderer/core/exported/web_view_impl.h
index 2f8e971ab224b36c6e464eb7524dd3d4c6b76f8c..4a9664d0ce5de431d9638e4145a21091cea78fd1 100644
--- a/third_party/blink/renderer/core/exported/web_view_impl.h
+++ b/third_party/blink/renderer/core/exported/web_view_impl.h
@@ -418,6 +418,7 @@ class CORE_EXPORT WebViewImpl final : public WebView,
   LocalDOMWindow* PagePopupWindow() const;
 
   PageScheduler* Scheduler() const override;
+  void SetSchedulerThrottling(bool allowed) override;
   void SetVisibilityState(mojom::blink::PageVisibilityState visibility_state,
                           bool is_initial_state) override;
   mojom::blink::PageVisibilityState GetVisibilityState() override;
@@ -865,6 +866,8 @@ class CORE_EXPORT WebViewImpl final : public WebView,
   // If true, we send IPC messages when |preferred_size_| changes.
   bool send_preferred_size_changes_ = false;
 
+  bool scheduler_throttling_allowed_ = true;
+
   // Whether the preferred size may have changed and |UpdatePreferredSize| needs
   // to be called.
   bool needs_preferred_size_update_ = true;
