Bug 880854. Part 2: Support reflows/frame reconstruction in print/print-preview documents by promoting them to frame reconstruction of the whole document. r=mats

--HG--
extra : rebase_source : e81c5cd0f9da7bbcd876669c4b9de46dac825a5d

layout/base/nsCSSFrameConstructor.cpp

@@ -94,6 +94,7 @@
 #include "nsTransitionManager.h"
 #include "nsSVGIntegrationUtils.h"
 #include "nsViewportFrame.h"
+#include "nsPageContentFrame.h"
 #include <algorithm>
 
 #ifdef MOZ_XUL
@@ -1422,6 +1423,7 @@ nsCSSFrameConstructor::nsCSSFrameConstructor(nsIDocument *aDocument,
   , mHasRootAbsPosContainingBlock(false)
   , mObservingRefreshDriver(false)
   , mInStyleRefresh(false)
+  , mPromoteReflowsToReframeRoot(false)
   , mHoverGeneration(0)
   , mRebuildAllExtraHint(nsChangeHint(0))
   , mAnimationGeneration(0)
@@ -8060,6 +8062,17 @@ NeedToReframeForAddingOrRemovingTransform(nsIFrame* aFrame)
   return false;
 }
 
+static nsIFrame*
+FindReflowRootFor(nsIFrame* aFrame)
+{
+  for (nsIFrame* f = aFrame; f; f = f->GetParent()) {
+    if (f->GetStateBits() & NS_FRAME_REFLOW_ROOT) {
+      return f;
+    }
+  }
+  return nullptr;
+}
+
 nsresult
 nsCSSFrameConstructor::ProcessRestyledFrames(nsStyleChangeList& aChangeList)
 {
@@ -8119,6 +8132,21 @@ nsCSSFrameConstructor::ProcessRestyledFrames(nsStyleChangeList& aChangeList)
       }
     }
 
+    if (mPromoteReflowsToReframeRoot &&
+        (hint & (nsChangeHint_ReconstructFrame | nsChangeHint_NeedReflow))) {
+      nsIFrame* reflowRoot = FindReflowRootFor(frame);
+      if (!reflowRoot) {
+        // Reflow root is the viewport. Better reframe the document.
+        // We don't do this for elements which are inside a reflow root --- they
+        // should be OK.
+        nsIContent* root = mDocument->GetRootElement();
+        if (root) {
+          NS_UpdateHint(hint, nsChangeHint_ReconstructFrame);
+          content = root;
+        }
+      }
+    }
+
     if ((hint & nsChangeHint_AddOrRemoveTransform) && frame &&
         !(hint & nsChangeHint_ReconstructFrame)) {
       if (NeedToReframeForAddingOrRemovingTransform(frame)) {
@@ -12115,6 +12143,7 @@ nsCSSFrameConstructor::PostRebuildAllStyleDataEvent(nsChangeHint aExtraHint)
 
   mRebuildAllStyleData = true;
   NS_UpdateHint(mRebuildAllExtraHint, aExtraHint);
+
   // Get a restyle event posted if necessary
   PostRestyleEventInternal(false);
 }

layout/base/nsCSSFrameConstructor.h

@@ -19,7 +19,6 @@
 #include "nsCounterManager.h"
 #include "nsHashKeys.h"
 #include "nsThreadUtils.h"
-#include "nsPageContentFrame.h"
 #include "nsCSSPseudoElements.h"
 #include "RestyleTracker.h"
 #include "nsIAnonymousContentCreator.h"
@@ -383,6 +382,8 @@ public:
   nsIFrame* GetDocElementContainingBlock()
     { return mDocElementContainingBlock; }
 
+  void SetPromoteReflowsToReframeRoot(bool aPromote) { mPromoteReflowsToReframeRoot = aPromote; }
+
 private:
   struct FrameConstructionItem;
   class FrameConstructionItemList;
@@ -1885,6 +1886,8 @@ private:
   bool                mObservingRefreshDriver : 1;
   // True if we're in the middle of a nsRefreshDriver refresh
   bool                mInStyleRefresh : 1;
+  // True if reflows/frame reconstruction should be promoted to reframe the root element
+  bool                mPromoteReflowsToReframeRoot : 1;
   uint32_t            mHoverGeneration;
   nsChangeHint        mRebuildAllExtraHint;
 

layout/printing/nsPrintEngine.cpp

@@ -114,6 +114,7 @@ static const char kPrintingPromptService[] = "@mozilla.org/embedcomp/printingpro
 #include "nsIContentViewerContainer.h"
 #include "nsIContentViewer.h"
 #include "nsIDocumentViewerPrint.h"
+#include "nsCSSFrameConstructor.h"
 
 #include "nsFocusManager.h"
 #include "nsRange.h"
@@ -1778,13 +1779,14 @@ nsPrintEngine::SetupToPrintContent()
   if (didReconstruction) {
     FirePrintPreviewUpdateEvent();
   }
-  
+
   DUMP_DOC_LIST(("\nAfter Reflow------------------------------------------"));
   PR_PL(("\n"));
   PR_PL(("-------------------------------------------------------\n"));
   PR_PL(("\n"));
 
   CalcNumPrintablePages(mPrt->mNumPrintablePages);
+  PromoteReflowsToReframeRoot();
 
   PR_PL(("--- Printing %d pages\n", mPrt->mNumPrintablePages));
   DUMP_DOC_TREELAYOUT;
@@ -2349,6 +2351,19 @@ nsPrintEngine::CalcNumPrintablePages(int32_t& aNumPages)
     }
   }
 }
+
+void
+nsPrintEngine::PromoteReflowsToReframeRoot()
+{
+  for (uint32_t i=0; i<mPrt->mPrintDocList.Length(); i++) {
+    nsPrintObject* po = mPrt->mPrintDocList.ElementAt(i);
+    NS_ASSERTION(po, "nsPrintObject can't be null!");
+    if (po->mPresContext) {
+      po->mPresContext->PresShell()->FrameConstructor()->SetPromoteReflowsToReframeRoot(true);
+    }
+  }
+}
+
 //-----------------------------------------------------------------
 //-- Done: Reflow Methods
 //-----------------------------------------------------------------

layout/printing/nsPrintEngine.h

@@ -127,6 +127,7 @@ public:
   void CheckForChildFrameSets(nsPrintObject* aPO);
 
   void CalcNumPrintablePages(int32_t& aNumPages);
+  void PromoteReflowsToReframeRoot();
   void ShowPrintProgress(bool aIsForPrinting, bool& aDoNotify);
   nsresult CleanupOnFailure(nsresult aResult, bool aIsPrinting);
   // If FinishPrintPreview() fails, caller may need to reset the state of the

layout/style/nsAnimationManager.cpp

@@ -12,6 +12,7 @@
 #include "nsSMILKeySpline.h"
 #include "nsEventDispatcher.h"
 #include "nsCSSFrameConstructor.h"
+#include "nsLayoutUtils.h"
 #include <math.h>
 
 using namespace mozilla;