diff --git a/layout/generic/nsTextFrameThebes.cpp b/layout/generic/nsTextFrameThebes.cpp
index 13da4033f18..972648a7368 100644
--- a/layout/generic/nsTextFrameThebes.cpp
+++ b/layout/generic/nsTextFrameThebes.cpp
@@ -4960,18 +4960,18 @@ nsTextFrame::AddInlineMinWidthForFlow(nsIRenderingContext *aRenderingContext,
 nsTextFrame::AddInlineMinWidth(nsIRenderingContext *aRenderingContext,
                                nsIFrame::InlineMinWidthData *aData)
 {
-  AddInlineMinWidthForFlow(aRenderingContext, aData);
-  if (mTextRun && !(mTextRun->GetFlags() & nsTextFrameUtils::TEXT_IS_SIMPLE_FLOW)) {
-    // mTextRun did not cover all continuations of this frame.
-    // Measure all additional flows associated with this frame's content.
-    nsTextFrame* f = this;
-    for (;;) {
-      f = NS_STATIC_CAST(nsTextFrame*, f->GetNextContinuation());
-      if (!f)
-        break;
-      if (f->GetStateBits() & TEXT_IS_RUN_OWNER) {
-        f->AddInlineMinWidthForFlow(aRenderingContext, aData);
-      }
+  nsTextFrame* f;
+  gfxTextRun* lastTextRun = nsnull;
+  // nsContinuingTextFrame does nothing for AddInlineMinWidth; all text frames
+  // in the flow are handled right here.
+  for (f = this; f; f = NS_STATIC_CAST(nsTextFrame*, f->GetNextContinuation())) {
+    // f->mTextRun could be null if we haven't set up textruns yet for f.
+    // Except in OOM situations, lastTextRun will only be null for the first
+    // text frame.
+    if (f == this || f->mTextRun != lastTextRun) {
+      // This will process all the text frames that share the same textrun as f.
+      f->AddInlineMinWidthForFlow(aRenderingContext, aData);
+      lastTextRun = f->mTextRun;
     }
   }
 }
@@ -5049,18 +5049,18 @@ nsTextFrame::AddInlinePrefWidthForFlow(nsIRenderingContext *aRenderingContext,
 nsTextFrame::AddInlinePrefWidth(nsIRenderingContext *aRenderingContext,
                                 nsIFrame::InlinePrefWidthData *aData)
 {
-  AddInlinePrefWidthForFlow(aRenderingContext, aData);
-  if (mTextRun && !(mTextRun->GetFlags() & nsTextFrameUtils::TEXT_IS_SIMPLE_FLOW)) {
-    // mTextRun did not cover all continuations of this frame.
-    // Measure all additional flows associated with this frame's content.
-    nsTextFrame* f = this;
-    for (;;) {
-      f = NS_STATIC_CAST(nsTextFrame*, f->GetNextContinuation());
-      if (!f)
-        break;
-      if (f->GetStateBits() & TEXT_IS_RUN_OWNER) {
-        f->AddInlinePrefWidthForFlow(aRenderingContext, aData);
-      }
+  nsTextFrame* f;
+  gfxTextRun* lastTextRun = nsnull;
+  // nsContinuingTextFrame does nothing for AddInlineMinWidth; all text frames
+  // in the flow are handled right here.
+  for (f = this; f; f = NS_STATIC_CAST(nsTextFrame*, f->GetNextContinuation())) {
+    // f->mTextRun could be null if we haven't set up textruns yet for f.
+    // Except in OOM situations, lastTextRun will only be null for the first
+    // text frame.
+    if (f == this || f->mTextRun != lastTextRun) {
+      // This will process all the text frames that share the same textrun as f.
+      f->AddInlinePrefWidthForFlow(aRenderingContext, aData);
+      lastTextRun = f->mTextRun;
     }
   }
 }
diff --git a/layout/reftests/bugs/reftest.list b/layout/reftests/bugs/reftest.list
index a581ad70776..347a383cdc4 100644
--- a/layout/reftests/bugs/reftest.list
+++ b/layout/reftests/bugs/reftest.list
@@ -121,7 +121,7 @@ random == 328829-1.xhtml 328829-1-ref.xhtml # bug 369046 (intermittent)
 == 335628-1.html 335628-1-ref.html
 != 335628-2.xul 335628-2-ref.xul
 == 336147-1.html 336147-1-ref.html
-fails == 336736-1.html 336736-1-ref.html # something wrong with subpixel horizontal alignment (tracked in bug 336736)
+fails-if(MOZ_WIDGET_TOOLKIT=="cocoa") == 336736-1.html 336736-1-ref.html # something wrong with subpixel horizontal alignment (tracked in bug 336736)
 == 339289-1.html 339289-1-ref.html
 == 341043-1a.html 341043-1-ref.html
 != 341043-1b.html 341043-1-ref.html