--- a/layout/generic/nsBlockFrame.cpp
+++ b/layout/generic/nsBlockFrame.cpp
@@ -447,26 +447,16 @@ nsBlockFrame::List(FILE* out, const char
 
 nsresult
 nsBlockFrame::GetFrameName(nsAString& aResult) const
 {
   return MakeFrameName(NS_LITERAL_STRING("Block"), aResult);
 }
 #endif
 
-#ifdef DEBUG
-nsFrameState
-nsBlockFrame::GetDebugStateBits() const
-{
-  // We don't want to include our cursor flag in the bits the
-  // regression tester looks at
-  return nsContainerFrame::GetDebugStateBits() & ~NS_BLOCK_HAS_LINE_CURSOR;
-}
-#endif
-
 void
 nsBlockFrame::InvalidateFrame(uint32_t aDisplayItemKey)
 {
   if (nsSVGUtils::IsInSVGTextSubtree(this)) {
     NS_ASSERTION(GetParent()->IsSVGTextFrame(),
                  "unexpected block frame in SVG text");
     GetParent()->InvalidateFrame();
     return;

--- a/layout/generic/nsBlockFrame.h
+++ b/layout/generic/nsBlockFrame.h
@@ -152,17 +152,16 @@ public:
   void InvalidateFrameWithRect(const nsRect& aRect, uint32_t aDisplayItemKey = 0) override;
 
 #ifdef DEBUG_FRAME_DUMP
   void List(FILE* out = stderr, const char* aPrefix = "", uint32_t aFlags = 0) const override;
   nsresult GetFrameName(nsAString& aResult) const override;
 #endif
 
 #ifdef DEBUG
-  nsFrameState GetDebugStateBits() const override;
   const char* LineReflowStatusToString(LineReflowStatus aLineReflowStatus) const;
 #endif
 
 #ifdef ACCESSIBILITY
   mozilla::a11y::AccType AccessibleType() override;
 #endif
 
   // Line cursor methods to speed up line searching in which one query

--- a/layout/generic/nsFrame.cpp
+++ b/layout/generic/nsFrame.cpp
@@ -7806,65 +7806,16 @@ nsIFrame::RootFrameList(nsPresContext* a
     nsIFrame* frame = shell->FrameManager()->GetRootFrame();
     if(frame) {
       frame->List(out, aPrefix);
     }
   }
 }
 #endif
 
-#ifdef DEBUG
-nsFrameState
-nsFrame::GetDebugStateBits() const
-{
-  // We'll ignore these flags for the purposes of comparing frame state:
-  //
-  //   NS_FRAME_EXTERNAL_REFERENCE
-  //     because this is set by the event state manager or the
-  //     caret code when a frame is focused. Depending on whether
-  //     or not the regression tests are run as the focused window
-  //     will make this value vary randomly.
-#define IRRELEVANT_FRAME_STATE_FLAGS NS_FRAME_EXTERNAL_REFERENCE
-
-#define FRAME_STATE_MASK (~(IRRELEVANT_FRAME_STATE_FLAGS))
-
-  return GetStateBits() & FRAME_STATE_MASK;
-}
-
-void
-nsFrame::XMLQuote(nsString& aString)
-{
-  int32_t i, len = aString.Length();
-  for (i = 0; i < len; i++) {
-    char16_t ch = aString.CharAt(i);
-    if (ch == '<') {
-      nsAutoString tmp(NS_LITERAL_STRING("&lt;"));
-      aString.Cut(i, 1);
-      aString.Insert(tmp, i);
-      len += 3;
-      i += 3;
-    }
-    else if (ch == '>') {
-      nsAutoString tmp(NS_LITERAL_STRING("&gt;"));
-      aString.Cut(i, 1);
-      aString.Insert(tmp, i);
-      len += 3;
-      i += 3;
-    }
-    else if (ch == '\"') {
-      nsAutoString tmp(NS_LITERAL_STRING("&quot;"));
-      aString.Cut(i, 1);
-      aString.Insert(tmp, i);
-      len += 5;
-      i += 5;
-    }
-  }
-}
-#endif
-
 bool
 nsIFrame::IsVisibleForPainting(nsDisplayListBuilder* aBuilder) {
   if (!StyleVisibility()->IsVisible())
     return false;
   nsISelection* sel = aBuilder->GetBoundingSelection();
   return !sel || IsVisibleInSelection(sel);
 }
 

--- a/layout/generic/nsFrame.h
+++ b/layout/generic/nsFrame.h
@@ -489,18 +489,16 @@ public:
   void Trace(const char* aMethod, bool aEnter);
   void Trace(const char* aMethod, bool aEnter, const nsReflowStatus& aStatus);
   void TraceMsg(const char* fmt, ...) MOZ_FORMAT_PRINTF(2, 3);
 
   // Helper function that verifies that each frame in the list has the
   // NS_FRAME_IS_DIRTY bit set
   static void VerifyDirtyBitSet(const nsFrameList& aFrameList);
 
-  static void XMLQuote(nsString& aString);
-
   // Display Reflow Debugging
   static void* DisplayReflowEnter(nsPresContext*          aPresContext,
                                   nsIFrame*                aFrame,
                                   const ReflowInput& aReflowInput);
   static void* DisplayLayoutEnter(nsIFrame* aFrame);
   static void* DisplayIntrinsicISizeEnter(nsIFrame* aFrame,
                                           const char* aType);
   static void* DisplayIntrinsicSizeEnter(nsIFrame* aFrame,
@@ -723,21 +721,16 @@ public:
   // Helper function to return the index in parent of the frame's content
   // object. Returns -1 on error or if the frame doesn't have a content object
   static int32_t ContentIndexInContainer(const nsIFrame* aFrame);
 #endif
 
 #ifdef DEBUG
 public:
   /**
-   * Return the state bits that are relevant to regression tests (that
-   * is, those bits which indicate a real difference when they differ
-   */
-  nsFrameState GetDebugStateBits() const override;
-  /**
    * See if style tree verification is enabled. To enable style tree
    * verification add "styleverifytree:1" to your MOZ_LOG
    * environment variable (any non-zero debug level will work). Or,
    * call SetVerifyStyleTreeEnable with true.
    */
   static bool GetVerifyStyleTreeEnable();
 
   /**

--- a/layout/generic/nsIFrame.h
+++ b/layout/generic/nsIFrame.h
@@ -4545,21 +4545,16 @@ public:
    */
   static void RootFrameList(nsPresContext* aPresContext,
                             FILE* out = stderr, const char* aPrefix = "");
   virtual void DumpFrameTree() const;
   void DumpFrameTreeLimited() const;
 
   virtual nsresult  GetFrameName(nsAString& aResult) const = 0;
 #endif
-
-#ifdef DEBUG
-public:
-  virtual nsFrameState  GetDebugStateBits() const = 0;
-#endif
 };
 
 //----------------------------------------------------------------------
 
 /**
  * AutoWeakFrame can be used to keep a reference to a nsIFrame in a safe way.
  * Whenever an nsIFrame object is deleted, the AutoWeakFrames pointing
  * to it will be cleared.  AutoWeakFrame is for variables on the stack or

--- a/layout/generic/nsTextFrame.cpp
+++ b/layout/generic/nsTextFrame.cpp
@@ -10260,26 +10260,16 @@ nsTextFrame::List(FILE* out, const char*
 
   if (IsSelected()) {
     str += " SELECTED";
   }
   fprintf_stderr(out, "%s\n", str.get());
 }
 #endif
 
-#ifdef DEBUG
-nsFrameState
-nsTextFrame::GetDebugStateBits() const
-{
-  // mask out our emptystate flags; those are just caches
-  return nsFrame::GetDebugStateBits() &
-    ~(TEXT_WHITESPACE_FLAGS | TEXT_REFLOW_FLAGS);
-}
-#endif
-
 void
 nsTextFrame::AdjustOffsetsForBidi(int32_t aStart, int32_t aEnd)
 {
   AddStateBits(NS_FRAME_IS_BIDI);
   if (mContent->HasFlag(NS_HAS_FLOWLENGTH_PROPERTY)) {
     mContent->DeleteProperty(nsGkAtoms::flowlength);
     mContent->UnsetFlags(NS_HAS_FLOWLENGTH_PROPERTY);
   }

--- a/layout/generic/nsTextFrame.h
+++ b/layout/generic/nsTextFrame.h
@@ -167,20 +167,16 @@ public:
 #ifdef DEBUG_FRAME_DUMP
   void List(FILE* out = stderr,
             const char* aPrefix = "",
             uint32_t aFlags = 0) const override;
   nsresult GetFrameName(nsAString& aResult) const override;
   void ToCString(nsCString& aBuf, int32_t* aTotalContentLength) const;
 #endif
 
-#ifdef DEBUG
-  nsFrameState GetDebugStateBits() const override;
-#endif
-
   ContentOffsets CalcContentOffsetsFromFramePoint(const nsPoint& aPoint) override;
   ContentOffsets GetCharacterOffsetAtFramePoint(const nsPoint& aPoint);
 
   /**
    * This is called only on the primary text frame. It indicates that
    * the selection state of the given character range has changed.
    * Text in the range is unconditionally invalidated
    * (Selection::Repaint depends on this).