Bug 1586986 - Deliver 'fixed-bottom' offset to the top of the pres context on the foreground tab. r=geckoview-reviewers,tnikkel,snorp

The dynamic toolbar transition doesn't affect on background tabs since to
switch tabs the dynamic toolbar should be restored to its original state (i.e.,
completely visible state).

Differential Revision: https://phabricator.services.mozilla.com/D52336

--HG--
extra : moz-landing-system : lando

dom/ipc/BrowserChild.cpp

@@ -1349,6 +1349,21 @@ mozilla::ipc::IPCResult BrowserChild::RecvDynamicToolbarMaxHeightChanged(
   return IPC_OK();
 }
 
+mozilla::ipc::IPCResult BrowserChild::RecvDynamicToolbarOffsetChanged(
+    const ScreenIntCoord& aOffset) {
+#if defined(MOZ_WIDGET_ANDROID)
+  RefPtr<Document> document = GetTopLevelDocument();
+  if (!document) {
+    return IPC_OK();
+  }
+
+  if (nsPresContext* presContext = document->GetPresContext()) {
+    presContext->UpdateDynamicToolbarOffset(aOffset);
+  }
+#endif
+  return IPC_OK();
+}
+
 mozilla::ipc::IPCResult BrowserChild::RecvSuppressDisplayport(
     const bool& aEnabled) {
   if (RefPtr<PresShell> presShell = GetTopLevelPresShell()) {

dom/ipc/BrowserChild.h

@@ -293,6 +293,9 @@ class BrowserChild final : public nsMessageManagerScriptExecutor,
   mozilla::ipc::IPCResult RecvDynamicToolbarMaxHeightChanged(
       const mozilla::ScreenIntCoord& aHeight);
 
+  mozilla::ipc::IPCResult RecvDynamicToolbarOffsetChanged(
+      const mozilla::ScreenIntCoord& aOffset);
+
   mozilla::ipc::IPCResult RecvActivate();
 
   mozilla::ipc::IPCResult RecvDeactivate();

dom/ipc/BrowserParent.cpp

@@ -1097,6 +1097,12 @@ void BrowserParent::DynamicToolbarMaxHeightChanged(ScreenIntCoord aHeight) {
     Unused << SendDynamicToolbarMaxHeightChanged(aHeight);
   }
 }
+
+void BrowserParent::DynamicToolbarOffsetChanged(ScreenIntCoord aOffset) {
+  if (!mIsDestroyed) {
+    Unused << SendDynamicToolbarOffsetChanged(aOffset);
+  }
+}
 #endif
 
 void BrowserParent::HandleAccessKey(const WidgetKeyboardEvent& aEvent,

dom/ipc/BrowserParent.h

@@ -535,6 +535,7 @@ class BrowserParent final : public PBrowserParent,
 
 #if defined(MOZ_WIDGET_ANDROID)
   void DynamicToolbarMaxHeightChanged(ScreenIntCoord aHeight);
+  void DynamicToolbarOffsetChanged(ScreenIntCoord aOffset);
 #endif
 
   void Activate();

dom/ipc/PBrowser.ipdl

@@ -753,6 +753,8 @@ child:
 
     async DynamicToolbarMaxHeightChanged(ScreenIntCoord height);
 
+    async DynamicToolbarOffsetChanged(ScreenIntCoord height);
+
     async ParentActivated(bool aActivated);
 
     async SetKeyboardIndicators(UIStateChangeType showFocusRings);

layout/base/PresShell.cpp

@@ -10418,6 +10418,10 @@ static void SetPluginIsActive(nsISupports* aSupports, void* aClosure) {
 nsresult PresShell::SetIsActive(bool aIsActive) {
   MOZ_ASSERT(mDocument, "should only be called with a document");
 
+#if defined(MOZ_WIDGET_ANDROID)
+  const bool changed = mIsActive != aIsActive;
+#endif
+
   mIsActive = aIsActive;
 
   nsPresContext* presContext = GetPresContext();
@@ -10439,6 +10443,17 @@ nsresult PresShell::SetIsActive(bool aIsActive) {
     }
   }
 #endif  // #ifdef ACCESSIBILITY
+
+#if defined(MOZ_WIDGET_ANDROID)
+  if (changed && !aIsActive && presContext &&
+      presContext->IsRootContentDocumentCrossProcess()) {
+    if (BrowserChild* browserChild = BrowserChild::GetFrom(this)) {
+      // Reset the dynamic toolbar offset state.
+      presContext->UpdateDynamicToolbarOffset(0);
+    }
+  }
+#endif
+
   return rv;
 }
 

layout/base/nsPresContext.cpp

@@ -2535,6 +2535,19 @@ void nsPresContext::AdjustSizeForViewportUnits() {
       NSIntPixelsToAppUnits(mDynamicToolbarMaxHeight, mCurAppUnitsPerDevPixel);
 }
 
+void nsPresContext::UpdateDynamicToolbarOffset(ScreenIntCoord aOffset) {
+  MOZ_ASSERT(IsRootContentDocumentCrossProcess());
+  if (!mPresShell) {
+    return;
+  }
+
+  if (!HasDynamicToolbar()) {
+    return;
+  }
+
+  MOZ_ASSERT(-mDynamicToolbarMaxHeight <= aOffset && aOffset <= 0);
+}
+
 #ifdef DEBUG
 
 void nsPresContext::ValidatePresShellAndDocumentReleation() const {

layout/base/nsPresContext.h

@@ -392,6 +392,11 @@ class nsPresContext : public nsISupports,
     return mDynamicToolbarMaxHeight > 0;
   }
 
+  /*
+   * |aOffset| must be offset from the bottom edge of the ICB and it's negative.
+   */
+  void UpdateDynamicToolbarOffset(mozilla::ScreenIntCoord aOffset);
+
   /**
    * Return true if this presentation context is a paginated
    * context.

mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoSession.java

@@ -222,7 +222,7 @@ public class GeckoSession implements Parcelable {
         @WrapForJNI(calledFrom = "ui", dispatchTo = "current")
         public native void setMaxToolbarHeight(int height);
 
-        @WrapForJNI(calledFrom = "ui", dispatchTo = "current")
+        @WrapForJNI(calledFrom = "ui", dispatchTo = "gecko")
         public native void setFixedBottomOffset(int offset);
 
         @WrapForJNI(calledFrom = "ui", dispatchTo = "current")

view/nsView.cpp

@@ -999,6 +999,43 @@ void nsView::DynamicToolbarMaxHeightChanged(ScreenIntCoord aHeight) {
   nsContentUtils::CallOnAllRemoteChildren(
       window, NotifyDynamicToolbarMaxHeightChanged, &aHeight);
 }
+
+static bool NotifyDynamicToolbarOffsetChanged(
+    dom::BrowserParent* aBrowserParent, void* aArg) {
+  // Skip background tabs.
+  if (!aBrowserParent->GetDocShellIsActive()) {
+    return false;
+  }
+
+  ScreenIntCoord* offset = static_cast<ScreenIntCoord*>(aArg);
+  aBrowserParent->DynamicToolbarOffsetChanged(*offset);
+  return true;
+}
+
+void nsView::DynamicToolbarOffsetChanged(ScreenIntCoord aOffset) {
+  MOZ_ASSERT(XRE_IsParentProcess(),
+             "Should be only called for the browser parent process");
+  MOZ_ASSERT(this == mViewManager->GetRootView(),
+             "Should be called for the root view");
+
+  PresShell* presShell = mViewManager->GetPresShell();
+  if (!presShell) {
+    return;
+  }
+
+  dom::Document* document = presShell->GetDocument();
+  if (!document) {
+    return;
+  }
+
+  nsPIDOMWindowOuter* window = document->GetWindow();
+  if (!window) {
+    return;
+  }
+
+  nsContentUtils::CallOnAllRemoteChildren(
+      window, NotifyDynamicToolbarOffsetChanged, &aOffset);
+}
 #endif
 
 bool nsView::RequestWindowClose(nsIWidget* aWidget) {

view/nsView.h

@@ -452,6 +452,8 @@ class nsView final : public nsIWidgetListener {
 #if defined(MOZ_WIDGET_ANDROID)
   virtual void DynamicToolbarMaxHeightChanged(
       mozilla::ScreenIntCoord aHeight) override;
+  virtual void DynamicToolbarOffsetChanged(
+      mozilla::ScreenIntCoord aOffset) override;
 #endif
   virtual bool RequestWindowClose(nsIWidget* aWidget) override;
   MOZ_CAN_RUN_SCRIPT_BOUNDARY

widget/android/nsWindow.cpp

@@ -1090,11 +1090,18 @@ class nsWindow::LayerViewSupport final
   }
 
   void SetFixedBottomOffset(int32_t aOffset) {
-    MOZ_ASSERT(AndroidBridge::IsJavaUiThread());
+    if (mWindow) {
+      mWindow->UpdateDynamicToolbarOffset(ScreenIntCoord(aOffset));
+    }
 
-    if (RefPtr<UiCompositorControllerChild> child =
-            GetUiCompositorControllerChild()) {
-      child->SetFixedBottomOffset(aOffset);
+    if (RefPtr<nsThread> uiThread = GetAndroidUiThread()) {
+      uiThread->Dispatch(NS_NewRunnableFunction(
+          "LayerViewSupport::SetFixedBottomOffset", [this, offset = aOffset] {
+            if (RefPtr<UiCompositorControllerChild> child =
+                    GetUiCompositorControllerChild()) {
+              child->SetFixedBottomOffset(offset);
+            }
+          }));
     }
   }
 
@@ -2326,6 +2333,16 @@ void nsWindow::UpdateDynamicToolbarMaxHeight(ScreenIntCoord aHeight) {
   }
 }
 
+void nsWindow::UpdateDynamicToolbarOffset(ScreenIntCoord aOffset) {
+  if (mWidgetListener) {
+    mWidgetListener->DynamicToolbarOffsetChanged(aOffset);
+  }
+
+  if (mAttachedWidgetListener) {
+    mAttachedWidgetListener->DynamicToolbarOffsetChanged(aOffset);
+  }
+}
+
 nsresult nsWindow::SetPrefersReducedMotionOverrideForTest(bool aValue) {
   nsXPLookAndFeel::GetInstance()->SetPrefersReducedMotionOverrideForTest(
       aValue);

widget/android/nsWindow.h

@@ -330,6 +330,8 @@ class nsWindow final : public nsBaseWidget {
   nsresult SetPrefersReducedMotionOverrideForTest(bool aValue) override;
   nsresult ResetPrefersReducedMotionOverrideForTest() override;
 
+  void UpdateDynamicToolbarOffset(mozilla::ScreenIntCoord aOffset);
+
  protected:
   void BringToFront();
   nsWindow* FindTopLevel();

widget/nsIWidgetListener.cpp

@@ -38,6 +38,7 @@ void nsIWidgetListener::UIResolutionChanged() {}
 #if defined(MOZ_WIDGET_ANDROID)
 void nsIWidgetListener::DynamicToolbarMaxHeightChanged(ScreenIntCoord aHeight) {
 }
+void nsIWidgetListener::DynamicToolbarOffsetChanged(ScreenIntCoord aOffset) {}
 #endif
 
 void nsIWidgetListener::FullscreenWillChange(bool aInFullscreen) {}

widget/nsIWidgetListener.h

@@ -87,6 +87,7 @@ class nsIWidgetListener {
 
 #if defined(MOZ_WIDGET_ANDROID)
   virtual void DynamicToolbarMaxHeightChanged(mozilla::ScreenIntCoord aHeight);
+  virtual void DynamicToolbarOffsetChanged(mozilla::ScreenIntCoord aOffset);
 #endif
 
   /**