Separate SwipeRefreshHandler and ContentViewCore

content/browser/renderer_host/render_widget_host_view_android.cc

Index: content/browser/renderer_host/render_widget_host_view_android.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_android.cc b/content/browser/renderer_host/render_widget_host_view_android.cc
index c0daedb3742ad67bd53a166e75877f14c7c4db38..2c2d6b2d073fc22c5402243177c83cf3fe2c8970 100644
--- a/content/browser/renderer_host/render_widget_host_view_android.cc
+++ b/content/browser/renderer_host/render_widget_host_view_android.cc
@@ -55,6 +55,7 @@
 #include "content/browser/renderer_host/input/synthetic_gesture_target_android.h"
 #include "content/browser/renderer_host/input/web_input_event_builders_android.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
+#include "content/browser/renderer_host/render_view_host_delegate_view.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/common/gpu_host_messages.h"
@@ -337,10 +338,12 @@ std::unique_ptr<ui::TouchSelectionController> CreateSelectionController(
 }
 
 std::unique_ptr<OverscrollControllerAndroid> CreateOverscrollController(
+    ui::OverscrollRefreshHandler* overscroll_refresh_handler,
     ContentViewCoreImpl* content_view_core,
     float dpi_scale) {
-  return base::MakeUnique<OverscrollControllerAndroid>(content_view_core,
-                                                       dpi_scale);
+  return base::MakeUnique<OverscrollControllerAndroid>(
+      overscroll_refresh_handler,
+      content_view_core->GetWindowAndroid()->GetCompositor(), dpi_scale);
 }
 
 gfx::RectF GetSelectionRect(const ui::TouchSelectionController& controller) {
@@ -469,6 +472,14 @@ RenderWidgetHostViewAndroid::RenderWidgetHostViewAndroid(
   host_->SetView(this);
   SetContentViewCore(content_view_core);
 
+  ui::OverscrollRefreshHandler* handler =
+      host_->delegate()->GetDelegateView()->GetOverscrollRefreshHandler();

[boliu, 2016/12/06 16:06:45]

looks like host_->delegate() may be null, so need to null check here and below

And as stated elsewhere, also need to check that the compositor in CVC is
non-null

also content_view_core_ is guaranteed null here, so this will just crash
immediately, so definitely don't need this block of code here?

loads of null checks to add :p

[rlanday, 2016/12/06 19:01:16]

I'm not sure what you mean here; this is right after content_view_core_ is set
by SetContentViewCore, this block of code is needed or the OverscrollController
won't get created if the OverscrollRefreshHandler had already been set on the
WebContentsViewAndroid (I didn't have this block of code and I couldn't pull to
refresh on my phone)

I'll look into the null checks

[boliu, 2016/12/06 19:05:17]

oh oops, my bad :p

+  if (handler) {
+    overscroll_controller_ = CreateOverscrollController(
+        handler, content_view_core_,
+        ui::GetScaleFactorForNativeView(GetNativeView()));
+  }
+
   if (GetTextInputManager())
     GetTextInputManager()->AddObserver(this);
 }
@@ -1220,6 +1231,13 @@ void RenderWidgetHostViewAndroid::SetSynchronousCompositorClient(
   }
 }
 
+void RenderWidgetHostViewAndroid::OnOverscrollRefreshHandlerSet() {
+  DCHECK(!overscroll_controller_);
+  overscroll_controller_ = CreateOverscrollController(
+      host_->delegate()->GetDelegateView()->GetOverscrollRefreshHandler(),
+      content_view_core_, ui::GetScaleFactorForNativeView(GetNativeView()));
+}
+
 bool RenderWidgetHostViewAndroid::SupportsAnimation() const {
   // The synchronous (WebView) compositor does not have a proper browser
   // compositor with which to drive animations.
@@ -1815,12 +1833,6 @@ void RenderWidgetHostViewAndroid::SetContentViewCore(
 
   if (!selection_controller_)
     selection_controller_ = CreateSelectionController(this, content_view_core_);
-
-  if (!overscroll_controller_ &&
-      view_.GetWindowAndroid()->GetCompositor()) {
-    overscroll_controller_ = CreateOverscrollController(
-        content_view_core_, ui::GetScaleFactorForNativeView(GetNativeView()));
-  }
 }
 
 void RenderWidgetHostViewAndroid::RunAckCallbacks() {
@@ -1884,9 +1896,15 @@ void RenderWidgetHostViewAndroid::OnDetachedFromWindow() {
 
 void RenderWidgetHostViewAndroid::OnAttachCompositor() {
   DCHECK(content_view_core_);
-  if (!overscroll_controller_)
-    overscroll_controller_ = CreateOverscrollController(
-        content_view_core_, ui::GetScaleFactorForNativeView(GetNativeView()));
+  if (!overscroll_controller_) {
+    ui::OverscrollRefreshHandler* handler =
+        host_->delegate()->GetDelegateView()->GetOverscrollRefreshHandler();
+    if (handler) {
+      overscroll_controller_ = CreateOverscrollController(
+          handler, content_view_core_,
+          ui::GetScaleFactorForNativeView(GetNativeView()));
+    }
+  }
   ui::WindowAndroidCompositor* compositor =
       view_.GetWindowAndroid()->GetCompositor();
   delegated_frame_host_->RegisterFrameSinkHierarchy(