Bug 746421 - Make nsTextBoxFrames overflow area include the LOOSE_INK_EXTENTS of the text. r=jfkthame

gfx/src/nsFontMetrics.cpp

@@ -365,20 +365,20 @@ nsFontMetrics::DrawString(const PRUnichar* aString, PRUint32 aLength,
                   &provider, nsnull, nsnull);
 }
 
-nsBoundingMetrics
-nsFontMetrics::GetBoundingMetrics(const PRUnichar *aString, PRUint32 aLength,
-                                  nsRenderingContext *aContext)
+static nsBoundingMetrics
+GetTextBoundingMetrics(nsFontMetrics* aMetrics, const PRUnichar *aString, PRUint32 aLength,
+                       nsRenderingContext *aContext, gfxFont::BoundingBoxType aType)
 {
     if (aLength == 0)
         return nsBoundingMetrics();
 
     StubPropertyProvider provider;
-    AutoTextRun textRun(this, aContext, aString, aLength);
+    AutoTextRun textRun(aMetrics, aContext, aString, aLength);
     nsBoundingMetrics m;
     if (textRun.get()) {
         gfxTextRun::Metrics theMetrics =
             textRun->MeasureText(0, aLength,
-                                 gfxFont::TIGHT_HINTED_OUTLINE_EXTENTS,
+                                 aType,
                                  aContext->ThebesContext(), &provider);
 
         m.leftBearing  = NSToCoordFloor( theMetrics.mBoundingBox.X());
@@ -389,3 +389,19 @@ nsFontMetrics::GetBoundingMetrics(const PRUnichar *aString, PRUint32 aLength,
     }
     return m;
 }
+
+nsBoundingMetrics
+nsFontMetrics::GetBoundingMetrics(const PRUnichar *aString, PRUint32 aLength,
+                                  nsRenderingContext *aContext)
+{
+  return GetTextBoundingMetrics(this, aString, aLength, aContext, gfxFont::TIGHT_HINTED_OUTLINE_EXTENTS);
+  
+}
+
+nsBoundingMetrics
+nsFontMetrics::GetInkBoundsForVisualOverflow(const PRUnichar *aString, PRUint32 aLength,
+                                             nsRenderingContext *aContext)
+{
+  return GetTextBoundingMetrics(this, aString, aLength, aContext, gfxFont::LOOSE_INK_EXTENTS);
+}
+

gfx/src/nsFontMetrics.h

@@ -221,6 +221,12 @@ public:
                                          PRUint32 aLength,
                                          nsRenderingContext *aContext);
 
+    // Returns the LOOSE_INK_EXTENTS bounds of the text for determing the
+    // overflow area of the string.
+    nsBoundingMetrics GetInkBoundsForVisualOverflow(const PRUnichar *aString,
+                                                    PRUint32 aLength,
+                                                    nsRenderingContext *aContext);
+
     void SetTextRunRTL(bool aIsRTL) { mTextRunRTL = aIsRTL; }
     bool GetTextRunRTL() { return mTextRunRTL; }
 

layout/xul/base/src/nsTextBoxFrame.cpp

@@ -930,16 +930,32 @@ nsTextBoxFrame::DoLayout(nsBoxLayoutState& aBoxLayoutState)
     CalcDrawRect(*aBoxLayoutState.GetRenderingContext());
 
     const nsStyleText* textStyle = GetStyleText();
+    
+    nsRect bounds(nsPoint(0, 0), GetSize());
+    nsRect textRect = mTextDrawRect;
+    
+    nsRefPtr<nsFontMetrics> fontMet;
+    nsLayoutUtils::GetFontMetricsForFrame(this, getter_AddRefs(fontMet));
+    nsBoundingMetrics metrics = 
+      fontMet->GetInkBoundsForVisualOverflow(mTitle.get(), mTitle.Length(),
+                                             aBoxLayoutState.GetRenderingContext());
+
+    textRect.x -= metrics.leftBearing;
+    textRect.width = metrics.width;
+    // In DrawText() we always draw with the baseline at MaxAscent() (relative to mTextDrawRect), 
+    textRect.y += fontMet->MaxAscent() - metrics.ascent;
+    textRect.height = metrics.ascent + metrics.descent;
+
+    bounds.UnionRect(bounds, textRect);
+    nsOverflowAreas overflow(bounds, bounds);
+
     if (textStyle->mTextShadow) {
-      nsRect bounds(nsPoint(0, 0), GetSize());
-      nsOverflowAreas overflow(bounds, bounds);
       // Our scrollable overflow is our bounds; our visual overflow may
       // extend beyond that.
-      nsPoint origin(0,0);
       nsRect &vis = overflow.VisualOverflow();
       vis.UnionRect(vis, nsLayoutUtils::GetTextShadowRectsUnion(mTextDrawRect, this));
-      FinishAndStoreOverflow(overflow, GetSize());
     }
+    FinishAndStoreOverflow(overflow, GetSize());
 
     return rv;
 }
@@ -947,8 +963,7 @@ nsTextBoxFrame::DoLayout(nsBoxLayoutState& aBoxLayoutState)
 nsRect
 nsTextBoxFrame::GetComponentAlphaBounds()
 {
-  return nsLayoutUtils::GetTextShadowRectsUnion(mTextDrawRect, this,
-                                                nsLayoutUtils::EXCLUDE_BLUR_SHADOWS);
+  return GetVisualOverflowRectRelativeToSelf();
 }
 
 bool