Bug 1918310 - Remove class nsMathMLmsqrtFrame. r=emilio

This class is currently only used to override InheritAutomaticData() and
IsMrowLike(). This patch moves that directly in nsMathMLrootFrame.
Probably we should have the same behavior when ShouldUseRowFallback()
returns true, but this patch does not try and change anything.

Differential Revision: https://phabricator.services.mozilla.com/D222258

Author: fred-wang

layout/base/nsCSSFrameConstructor.cpp

@@ -4630,7 +4630,7 @@ nsCSSFrameConstructor::FindMathMLData(const Element& aElement,
       SIMPLE_MATHML_CREATE(mfenced_, NS_NewMathMLmrowFrame),
       SIMPLE_MATHML_CREATE(mmultiscripts_, NS_NewMathMLmmultiscriptsFrame),
       SIMPLE_MATHML_CREATE(mstyle_, NS_NewMathMLmrowFrame),
-      SIMPLE_MATHML_CREATE(msqrt_, NS_NewMathMLmsqrtFrame),
+      SIMPLE_MATHML_CREATE(msqrt_, NS_NewMathMLmrootFrame),
       SIMPLE_MATHML_CREATE(mroot_, NS_NewMathMLmrootFrame),
       SIMPLE_MATHML_CREATE(maction_, NS_NewMathMLmrowFrame),
       SIMPLE_MATHML_CREATE(mrow_, NS_NewMathMLmrowFrame),

layout/generic/FrameClasses.py

@@ -88,7 +88,6 @@
     Frame("nsMathMLmrootFrame", "None", MATHML_CONTAINER),
     Frame("nsMathMLmrowFrame", "None", MATHML_CONTAINER),
     Frame("nsMathMLmspaceFrame", "None", MATHML_CONTAINER | LEAF),
-    Frame("nsMathMLmsqrtFrame", "None", MATHML_CONTAINER),
     Frame("nsMathMLmtableFrame", "Table", TABLE | MATHML),
     Frame("nsMathMLmtableWrapperFrame", "TableWrapper", BLOCK | MATHML),
     Frame("nsMathMLmtdFrame", "TableCell", TABLE_CELL | MATHML),

layout/mathml/moz.build

@@ -24,7 +24,6 @@ UNIFIED_SOURCES += [
     "nsMathMLmrootFrame.cpp",
     "nsMathMLmrowFrame.cpp",
     "nsMathMLmspaceFrame.cpp",
-    "nsMathMLmsqrtFrame.cpp",
     "nsMathMLmtableFrame.cpp",
     "nsMathMLmunderoverFrame.cpp",
     "nsMathMLOperators.cpp",

layout/mathml/nsMathMLParts.h

@@ -52,8 +52,6 @@ nsContainerFrame* NS_NewMathMLmtdFrame(mozilla::PresShell* aPresShell,
                                        nsTableFrame* aTableFrame);
 nsContainerFrame* NS_NewMathMLmtdInnerFrame(mozilla::PresShell* aPresShell,
                                             mozilla::ComputedStyle* aStyle);
-nsIFrame* NS_NewMathMLmsqrtFrame(mozilla::PresShell* aPresShell,
-                                 mozilla::ComputedStyle* aStyle);
 nsIFrame* NS_NewMathMLmrootFrame(mozilla::PresShell* aPresShell,
                                  mozilla::ComputedStyle* aStyle);
 nsIFrame* NS_NewMathMLmencloseFrame(mozilla::PresShell* aPresShell,

layout/mathml/nsMathMLmrootFrame.cpp

@@ -29,8 +29,8 @@ nsIFrame* NS_NewMathMLmrootFrame(PresShell* aPresShell, ComputedStyle* aStyle) {
 NS_IMPL_FRAMEARENA_HELPERS(nsMathMLmrootFrame)
 
 nsMathMLmrootFrame::nsMathMLmrootFrame(ComputedStyle* aStyle,
-                                       nsPresContext* aPresContext, ClassID aID)
-    : nsMathMLContainerFrame(aStyle, aPresContext, aID) {}
+                                       nsPresContext* aPresContext)
+    : nsMathMLContainerFrame(aStyle, aPresContext, kClassID) {}
 
 nsMathMLmrootFrame::~nsMathMLmrootFrame() = default;
 
@@ -58,6 +58,26 @@ bool nsMathMLmrootFrame::ShouldUseRowFallback() {
   return !indexFrame || indexFrame->GetNextSibling();
 }
 
+bool nsMathMLmrootFrame::IsMrowLike() {
+  bool isRootWithIndex = GetContent()->IsMathMLElement(nsGkAtoms::mroot_);
+  if (isRootWithIndex) {
+    return false;
+  }
+  return mFrames.FirstChild() != mFrames.LastChild() || !mFrames.FirstChild();
+}
+
+NS_IMETHODIMP
+nsMathMLmrootFrame::InheritAutomaticData(nsIFrame* aParent) {
+  nsMathMLContainerFrame::InheritAutomaticData(aParent);
+
+  bool isRootWithIndex = GetContent()->IsMathMLElement(nsGkAtoms::mroot_);
+  if (!isRootWithIndex) {
+    mPresentationData.flags |= NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY;
+  }
+
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 nsMathMLmrootFrame::TransmitAutomaticData() {
   bool isRootWithIndex = GetContent()->IsMathMLElement(nsGkAtoms::mroot_);

layout/mathml/nsMathMLmrootFrame.h

@@ -31,6 +31,9 @@ class nsMathMLmrootFrame : public nsMathMLContainerFrame {
   virtual void Init(nsIContent* aContent, nsContainerFrame* aParent,
                     nsIFrame* aPrevInFlow) override;
 
+  NS_IMETHOD
+  InheritAutomaticData(nsIFrame* aParent) final;
+
   NS_IMETHOD
   TransmitAutomaticData() override;
 
@@ -47,15 +50,15 @@ class nsMathMLmrootFrame : public nsMathMLContainerFrame {
 
  protected:
   explicit nsMathMLmrootFrame(ComputedStyle* aStyle,
-                              nsPresContext* aPresContext,
-                              ClassID aID = kClassID);
+                              nsPresContext* aPresContext);
   virtual ~nsMathMLmrootFrame();
 
   nsMathMLChar mSqrChar;
   nsRect mBarRect;
 
  private:
   bool ShouldUseRowFallback();
+  bool IsMrowLike() final;
   nsresult Place(DrawTarget* aDrawTarget, const PlaceFlags& aFlags,
                  ReflowOutput& aDesiredSize) final;
 };