Bug 445685 - Improve performance with large numbers of text fragments. r=jwatt,sr=roc

layout/svg/base/src/nsSVGGlyphFrame.cpp

@@ -229,8 +229,11 @@ NS_IMETHODIMP
 nsSVGGlyphFrame::DidSetStyleContext()
 {
   nsSVGGlyphFrameBase::DidSetStyleContext();
-  ClearTextRun();
+
-  NotifyGlyphMetricsChange();
+  if (!(GetStateBits() & NS_FRAME_FIRST_REFLOW)) {
+    ClearTextRun();
+    NotifyGlyphMetricsChange();
+  }
 
   return NS_OK;
 }
@@ -459,8 +462,6 @@ nsSVGGlyphFrame::InitialUpdate()
   NS_ASSERTION(!(mState & NS_FRAME_IN_REFLOW),
                "We don't actually participate in reflow");
 
-  NotifyGlyphMetricsChange();
-
   // Do unset the various reflow bits, though.
   mState &= ~(NS_FRAME_FIRST_REFLOW | NS_FRAME_IS_DIRTY |
               NS_FRAME_HAS_DIRTY_CHILDREN);

layout/svg/base/src/nsSVGTextFrame.cpp

@@ -266,6 +266,16 @@ nsSVGTextFrame::UpdateCoveredRegion()
   return nsSVGTextFrameBase::UpdateCoveredRegion();
 }
 
+NS_IMETHODIMP
+nsSVGTextFrame::InitialUpdate()
+{
+  nsresult rv = nsSVGTextFrameBase::InitialUpdate();
+  
+  UpdateGlyphPositioning(PR_FALSE);
+
+  return rv;
+}  
+
 NS_IMETHODIMP
 nsSVGTextFrame::GetBBox(nsIDOMSVGRect **_retval)
 {

layout/svg/base/src/nsSVGTextFrame.h

@@ -87,6 +87,7 @@ public:
   NS_IMETHOD PaintSVG(nsSVGRenderState* aContext, nsRect *aDirtyRect);
   NS_IMETHOD GetFrameForPointSVG(float x, float y, nsIFrame** hit);  
   NS_IMETHOD UpdateCoveredRegion();
+  NS_IMETHOD InitialUpdate();
   NS_IMETHOD GetBBox(nsIDOMSVGRect **_retval);
   
   // nsSVGContainerFrame methods: