Bug 1878976 - Remove plugin-related code in EventStateManager; r=emilio

`nsIFrame::GetCursor()` can never return `Nothing()` after bug 1687239, which
removes `nsPluginFrame`. Therefore `mLastFrameConsumedSetCursor` in
`EventStateManager` can never be true.

Differential Revision: https://phabricator.services.mozilla.com/D200890

dom/events/EventStateManager.cpp

@@ -4348,23 +4348,9 @@ void EventStateManager::UpdateCursor(nsPresContext* aPresContext,
     // If not locked, look for correct cursor
     nsPoint pt = nsLayoutUtils::GetEventCoordinatesRelativeTo(
         aEvent, RelativeTo{aTargetFrame});
-    Maybe<nsIFrame::Cursor> framecursor = aTargetFrame->GetCursor(pt);
-    // Avoid setting cursor when the mouse is over a windowless plugin.
-    if (!framecursor) {
-      if (XRE_IsContentProcess()) {
-        mLastFrameConsumedSetCursor = true;
-      }
-      return;
-    }
-    // Make sure cursors get reset after the mouse leaves a
-    // windowless plugin frame.
-    if (mLastFrameConsumedSetCursor) {
-      ClearCachedWidgetCursor(aTargetFrame);
-      mLastFrameConsumedSetCursor = false;
-    }
-
+    const nsIFrame::Cursor framecursor = aTargetFrame->GetCursor(pt);
     const CursorImage customCursor =
-        ComputeCustomCursor(aPresContext, aEvent, *aTargetFrame, *framecursor);
+        ComputeCustomCursor(aPresContext, aEvent, *aTargetFrame, framecursor);
 
     // If the current cursor is from the same frame, and it is now
     // loading some new image for the cursor, we should wait for a
@@ -4375,7 +4361,7 @@ void EventStateManager::UpdateCursor(nsPresContext* aPresContext,
             TimeDuration::FromMilliseconds(kCursorLoadingTimeout)) {
       return;
     }
-    cursor = framecursor->mCursor;
+    cursor = framecursor.mCursor;
     container = std::move(customCursor.mContainer);
     resolution = customCursor.mResolution;
     hotspot = Some(customCursor.mHotspot);

dom/events/EventStateManager.h

@@ -1233,7 +1233,6 @@ class EventStateManager : public nsSupportsWeakReference, public nsIObserver {
 
   // These variables are only relevant if we're the cursor-setting manager.
   StyleCursorKind mLockCursor;
-  bool mLastFrameConsumedSetCursor = false;
   bool mHidingCursorWhileTyping = false;
 
   // Last mouse event screen point (in device pixel) when mouse was locked, used

layout/forms/nsImageControlFrame.cpp

@@ -45,7 +45,7 @@ class nsImageControlFrame final : public nsImageFrame,
   }
 #endif
 
-  Maybe<Cursor> GetCursor(const nsPoint&) final;
+  Cursor GetCursor(const nsPoint&) final;
 
   // nsIFormContromFrame
   void SetFocus(bool aOn, bool aRepaint) final;
@@ -137,12 +137,12 @@ nsresult nsImageControlFrame::HandleEvent(nsPresContext* aPresContext,
 
 void nsImageControlFrame::SetFocus(bool aOn, bool aRepaint) {}
 
-Maybe<nsIFrame::Cursor> nsImageControlFrame::GetCursor(const nsPoint&) {
+nsIFrame::Cursor nsImageControlFrame::GetCursor(const nsPoint&) {
   StyleCursorKind kind = StyleUI()->Cursor().keyword;
   if (kind == StyleCursorKind::Auto) {
     kind = StyleCursorKind::Pointer;
   }
-  return Some(Cursor{kind, AllowCustomCursorImage::Yes});
+  return Cursor{kind, AllowCustomCursorImage::Yes};
 }
 
 nsresult nsImageControlFrame::SetFormProperty(nsAtom* aName,

layout/generic/nsFrameSetFrame.cpp

@@ -89,7 +89,7 @@ class nsHTMLFramesetBorderFrame final : public nsLeafFrame {
                                WidgetGUIEvent* aEvent,
                                nsEventStatus* aEventStatus) override;
 
-  Maybe<Cursor> GetCursor(const nsPoint&) override;
+  Cursor GetCursor(const nsPoint&) override;
 
   virtual void BuildDisplayList(nsDisplayListBuilder* aBuilder,
                                 const nsDisplayListSet& aLists) override;
@@ -630,13 +630,13 @@ nsresult nsHTMLFramesetFrame::HandleEvent(nsPresContext* aPresContext,
   return NS_OK;
 }
 
-Maybe<nsIFrame::Cursor> nsHTMLFramesetFrame::GetCursor(const nsPoint&) {
+nsIFrame::Cursor nsHTMLFramesetFrame::GetCursor(const nsPoint&) {
   auto kind = StyleCursorKind::Default;
   if (mDragger) {
     kind = mDragger->mVertical ? StyleCursorKind::EwResize
                                : StyleCursorKind::NsResize;
   }
-  return Some(Cursor{kind, AllowCustomCursorImage::No});
+  return Cursor{kind, AllowCustomCursorImage::No};
 }
 
 void nsHTMLFramesetFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
@@ -1454,12 +1454,12 @@ nsresult nsHTMLFramesetBorderFrame::HandleEvent(nsPresContext* aPresContext,
   return NS_OK;
 }
 
-Maybe<nsIFrame::Cursor> nsHTMLFramesetBorderFrame::GetCursor(const nsPoint&) {
+nsIFrame::Cursor nsHTMLFramesetBorderFrame::GetCursor(const nsPoint&) {
   auto kind = StyleCursorKind::Default;
   if (mCanResize) {
     kind = mVertical ? StyleCursorKind::EwResize : StyleCursorKind::NsResize;
   }
-  return Some(Cursor{kind, AllowCustomCursorImage::No});
+  return Cursor{kind, AllowCustomCursorImage::No};
 }
 
 #ifdef DEBUG_FRAME_DUMP

layout/generic/nsFrameSetFrame.h

@@ -88,7 +88,7 @@ class nsHTMLFramesetFrame final : public nsContainerFrame {
                                mozilla::WidgetGUIEvent* aEvent,
                                nsEventStatus* aEventStatus) override;
 
-  mozilla::Maybe<Cursor> GetCursor(const nsPoint&) override;
+  Cursor GetCursor(const nsPoint&) override;
 
   virtual void BuildDisplayList(nsDisplayListBuilder* aBuilder,
                                 const nsDisplayListSet& aLists) override;

layout/generic/nsIFrame.cpp

@@ -5890,7 +5890,7 @@ StyleTouchAction nsIFrame::UsedTouchAction() const {
   return disp.mTouchAction;
 }
 
-Maybe<nsIFrame::Cursor> nsIFrame::GetCursor(const nsPoint&) {
+nsIFrame::Cursor nsIFrame::GetCursor(const nsPoint&) {
   StyleCursorKind kind = StyleUI()->Cursor().keyword;
   if (kind == StyleCursorKind::Auto) {
     // If this is editable, I-beam cursor is better for most elements.
@@ -5903,7 +5903,7 @@ Maybe<nsIFrame::Cursor> nsIFrame::GetCursor(const nsPoint&) {
     kind = StyleCursorKind::VerticalText;
   }
 
-  return Some(Cursor{kind, AllowCustomCursorImage::Yes});
+  return Cursor{kind, AllowCustomCursorImage::Yes};
 }
 
 // Resize and incremental reflow

layout/generic/nsIFrame.h

@@ -2338,7 +2338,7 @@ class nsIFrame : public nsQueryFrame {
   /**
    * Get the cursor for a given frame.
    */
-  virtual Maybe<Cursor> GetCursor(const nsPoint&);
+  virtual Cursor GetCursor(const nsPoint&);
 
   /**
    * Get a point (in the frame's coordinate space) given an offset into

layout/generic/nsImageFrame.cpp

@@ -2773,7 +2773,7 @@ nsresult nsImageFrame::HandleEvent(nsPresContext* aPresContext,
                                              aEventStatus);
 }
 
-Maybe<nsIFrame::Cursor> nsImageFrame::GetCursor(const nsPoint& aPoint) {
+nsIFrame::Cursor nsImageFrame::GetCursor(const nsPoint& aPoint) {
   nsImageMap* map = GetImageMap();
   if (!map) {
     return nsIFrame::GetCursor(aPoint);
@@ -2796,7 +2796,7 @@ Maybe<nsIFrame::Cursor> nsImageFrame::GetCursor(const nsPoint& aPoint) {
   if (kind == StyleCursorKind::Auto) {
     kind = StyleCursorKind::Default;
   }
-  return Some(Cursor{kind, AllowCustomCursorImage::Yes, std::move(areaStyle)});
+  return Cursor{kind, AllowCustomCursorImage::Yes, std::move(areaStyle)};
 }
 
 nsresult nsImageFrame::AttributeChanged(int32_t aNameSpaceID,

layout/generic/nsImageFrame.h

@@ -90,7 +90,7 @@ class nsImageFrame : public nsAtomicContainerFrame, public nsIReflowCallback {
                               nsIContent** aContent) final;
   nsresult HandleEvent(nsPresContext*, mozilla::WidgetGUIEvent*,
                        nsEventStatus*) override;
-  mozilla::Maybe<Cursor> GetCursor(const nsPoint&) override;
+  Cursor GetCursor(const nsPoint&) override;
   nsresult AttributeChanged(int32_t aNameSpaceID, nsAtom* aAttribute,
                             int32_t aModType) final;
 

layout/generic/nsTextFrame.cpp

@@ -4368,7 +4368,7 @@ NS_IMPL_FRAMEARENA_HELPERS(nsContinuingTextFrame)
 
 nsTextFrame::~nsTextFrame() = default;
 
-Maybe<nsIFrame::Cursor> nsTextFrame::GetCursor(const nsPoint& aPoint) {
+nsIFrame::Cursor nsTextFrame::GetCursor(const nsPoint& aPoint) {
   StyleCursorKind kind = StyleUI()->Cursor().keyword;
   if (kind == StyleCursorKind::Auto) {
     if (!IsSelectable(nullptr)) {
@@ -4378,7 +4378,7 @@ Maybe<nsIFrame::Cursor> nsTextFrame::GetCursor(const nsPoint& aPoint) {
                                            : StyleCursorKind::Text;
     }
   }
-  return Some(Cursor{kind, AllowCustomCursorImage::Yes});
+  return Cursor{kind, AllowCustomCursorImage::Yes};
 }
 
 nsTextFrame* nsTextFrame::LastInFlow() const {

layout/generic/nsTextFrame.h

@@ -219,7 +219,7 @@ class nsTextFrame : public nsIFrame {
 
   void Destroy(DestroyContext&) override;
 
-  mozilla::Maybe<Cursor> GetCursor(const nsPoint&) final;
+  Cursor GetCursor(const nsPoint&) final;
 
   nsresult CharacterDataChanged(const CharacterDataChangeInfo&) final;
 

layout/xul/tree/nsTreeBodyFrame.cpp

@@ -2220,7 +2220,7 @@ nscoord nsTreeBodyFrame::CalcHorzWidth(const ScrollParts& aParts) {
   return width;
 }
 
-Maybe<nsIFrame::Cursor> nsTreeBodyFrame::GetCursor(const nsPoint& aPoint) {
+nsIFrame::Cursor nsTreeBodyFrame::GetCursor(const nsPoint& aPoint) {
   // Check the GetScriptHandlingObject so we don't end up running code when
   // the document is a zombie.
   bool dummy;
@@ -2237,8 +2237,7 @@ Maybe<nsIFrame::Cursor> nsTreeBodyFrame::GetCursor(const nsPoint& aPoint) {
       if (kind == StyleCursorKind::Auto) {
         kind = StyleCursorKind::Default;
       }
-      return Some(
-          Cursor{kind, AllowCustomCursorImage::Yes, std::move(childContext)});
+      return Cursor{kind, AllowCustomCursorImage::Yes, std::move(childContext)};
     }
   }
   return SimpleXULLeafFrame::GetCursor(aPoint);

layout/xul/tree/nsTreeBodyFrame.h

@@ -159,7 +159,7 @@ class nsTreeBodyFrame final : public mozilla::SimpleXULLeafFrame,
             nsIFrame* aPrevInFlow) override;
   void Destroy(DestroyContext&) override;
 
-  mozilla::Maybe<Cursor> GetCursor(const nsPoint&) override;
+  Cursor GetCursor(const nsPoint&) override;
 
   nsresult HandleEvent(nsPresContext* aPresContext,
                        mozilla::WidgetGUIEvent* aEvent,