Bug 1516368 - Change SetResolutionAndScaleTo to take an enum instead of an nsAtoms*. r=botond

There is no reason to use nsAtoms*, it's error prone, i.e. the function
can take arbitrary nsAtoms*.

Depends on D15339

Differential Revision: https://phabricator.services.mozilla.com/D15340

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

dom/base/nsDOMWindowUtils.cpp

@@ -548,7 +548,8 @@ nsDOMWindowUtils::SetResolutionAndScaleTo(float aResolution) {
     return NS_ERROR_FAILURE;
   }
 
-  presShell->SetResolutionAndScaleTo(aResolution, nsGkAtoms::other);
+  presShell->SetResolutionAndScaleTo(aResolution,
+                                     nsIPresShell::ChangeOrigin::eOther);
 
   return NS_OK;
 }

dom/base/nsDocument.cpp

@@ -10148,7 +10148,8 @@ void nsIDocument::CleanupFullscreenState() {
   // Restore the zoom level that was in place prior to entering fullscreen.
   if (nsIPresShell* shell = GetShell()) {
     if (shell->GetMobileViewportManager()) {
-      shell->SetResolutionAndScaleTo(mSavedResolution, nsGkAtoms::restore);
+      shell->SetResolutionAndScaleTo(mSavedResolution,
+                                     nsIPresShell::ChangeOrigin::eRestore);
     }
   }
 
@@ -10546,7 +10547,7 @@ bool nsIDocument::ApplyFullscreen(UniquePtr<FullscreenRequest> aRequest) {
         // Save the previous resolution so it can be restored.
         child->mSavedResolution = shell->GetResolution();
         shell->SetResolutionAndScaleTo(manager->ComputeIntrinsicResolution(),
-                                       nsGkAtoms::other);
+                                       nsIPresShell::ChangeOrigin::eOther);
       }
     }
 

gfx/layers/apz/util/APZCCallbackHelper.cpp

@@ -318,7 +318,8 @@ void APZCCallbackHelper::UpdateRootFrame(const RepaintRequest& aRequest) {
     // last paint.
     presShellResolution =
         aRequest.GetPresShellResolution() * aRequest.GetAsyncZoom().scale;
-    shell->SetResolutionAndScaleTo(presShellResolution, nsGkAtoms::apz);
+    shell->SetResolutionAndScaleTo(presShellResolution,
+                                   nsIPresShell::ChangeOrigin::eApz);
   }
 
   // Do this as late as possible since scrolling can flush layout. It also

layout/base/MobileViewportManager.cpp

@@ -329,7 +329,8 @@ void MobileViewportManager::UpdateResolution(
   if (newZoom) {
     LayoutDeviceToLayerScale resolution = ZoomToResolution(*newZoom, cssToDev);
     MVM_LOG("%p: setting resolution %f\n", this, resolution.scale);
-    mPresShell->SetResolutionAndScaleTo(resolution.scale, nsGkAtoms::other);
+    mPresShell->SetResolutionAndScaleTo(resolution.scale,
+                                        nsIPresShell::ChangeOrigin::eOther);
 
     MVM_LOG("%p: New zoom is %f\n", this, newZoom->scale);
   }

layout/base/PresShell.cpp

@@ -5157,7 +5157,7 @@ void PresShell::SetIgnoreViewportScrolling(bool aIgnore) {
 }
 
 nsresult PresShell::SetResolutionAndScaleTo(float aResolution,
-                                            nsAtom* aOrigin) {
+                                            ChangeOrigin aOrigin) {
   if (!(aResolution > 0.0)) {
     return NS_ERROR_ILLEGAL_VALUE;
   }
@@ -5171,7 +5171,7 @@ nsresult PresShell::SetResolutionAndScaleTo(float aResolution,
   if (mMobileViewportManager) {
     mMobileViewportManager->ResolutionUpdated();
   }
-  if (aOrigin != nsGkAtoms::apz) {
+  if (aOrigin != ChangeOrigin::eApz) {
     mResolutionUpdated = true;
   }
   if (auto* window = nsGlobalWindowInner::Cast(mDocument->GetInnerWindow())) {

layout/base/PresShell.h

@@ -195,7 +195,8 @@ class PresShell final : public nsIPresShell,
 
   void SetIgnoreViewportScrolling(bool aIgnore) override;
 
-  nsresult SetResolutionAndScaleTo(float aResolution, nsAtom* aOrigin) override;
+  nsresult SetResolutionAndScaleTo(float aResolution,
+                                   ChangeOrigin aOrigin) override;
   bool IsResolutionUpdated() const override { return mResolutionUpdated; }
   void SetResolutionUpdated(bool aUpdated) override {
     mResolutionUpdated = aUpdated;

layout/base/nsIPresShell.h

@@ -1371,12 +1371,17 @@ class nsIPresShell : public nsStubDocumentObserver {
    * The resolution defaults to 1.0.
    *
    * |aOrigin| specifies who originated the resolution change. For changes
-   * sent by APZ, pass nsGkAtoms::apz. For changes sent by the main thread,
-   * use pass nsGkAtoms::other or nsGkAtoms::restore (similar to the |aOrigin|
-   * parameter of nsIScrollableFrame::ScrollToCSSPixels()).
+   * sent by APZ, pass ChangeOrigin::eApz. For changes sent by the main thread,
+   * use pass ChangeOrigin::Other or ChangeOrigin::Restore (similar to the
+   * |aOrigin| parameter of nsIScrollableFrame::ScrollToCSSPixels()).
    */
+  enum class ChangeOrigin : uint8_t {
+    eApz,
+    eRestore,
+    eOther,
+  };
   virtual nsresult SetResolutionAndScaleTo(float aResolution,
-                                           nsAtom* aOrigin) = 0;
+                                           ChangeOrigin aOrigin) = 0;
   float GetResolution() const { return mResolution.valueOr(1.0); }
   virtual float GetCumulativeResolution() = 0;
 

layout/generic/nsGfxScrollFrame.cpp

@@ -6162,7 +6162,7 @@ void ScrollFrameHelper::RestoreState(PresState* aState) {
   if (mIsRoot) {
     nsIPresShell* presShell = mOuter->PresShell();
     presShell->SetResolutionAndScaleTo(aState->resolution(),
-                                       nsGkAtoms::restore);
+                                       nsIPresShell::ChangeOrigin::eRestore);
   }
 }