diff --git a/layout/base/nsCSSFrameConstructor.cpp b/layout/base/nsCSSFrameConstructor.cpp
index d8daac37f8d..cd68bda5837 100644
--- a/layout/base/nsCSSFrameConstructor.cpp
+++ b/layout/base/nsCSSFrameConstructor.cpp
@@ -76,6 +76,7 @@
 #include "nsAutoPtr.h"
 #include "nsBoxFrame.h"
 #include "nsBoxLayout.h"
+#include "nsFlexContainerFrame.h"
 #include "nsImageFrame.h"
 #include "nsIObjectLoadingContent.h"
 #include "nsIPrincipal.h"
@@ -101,7 +102,6 @@
 #include "nsIDOMXULDocument.h"
 #include "nsIXULDocument.h"
 #endif
-#include "nsFlexContainerFrame.h"
 #ifdef ACCESSIBILITY
 #include "nsAccessibilityService.h"
 #endif
diff --git a/layout/generic/Makefile.in b/layout/generic/Makefile.in
index efe449b4788..be0c1399fff 100644
--- a/layout/generic/Makefile.in
+++ b/layout/generic/Makefile.in
@@ -27,6 +27,7 @@ CPPSRCS		= \
 		nsColumnSetFrame.cpp \
 		nsContainerFrame.cpp \
 		nsFirstLetterFrame.cpp \
+		nsFlexContainerFrame.cpp \
 		nsFloatManager.cpp \
 		nsFontInflationData.cpp \
 		nsFrame.cpp \
@@ -62,10 +63,6 @@ CPPSRCS		= \
 		nsVideoFrame.cpp \
 		$(NULL)
 
-CPPSRCS		+= \
-		nsFlexContainerFrame.cpp \
-		$(NULL)
-
 ifeq (cocoa,$(MOZ_WIDGET_TOOLKIT))
 CMMSRCS		+= \
 		nsPluginUtilsOSX.mm \
diff --git a/layout/generic/nsHTMLReflowState.cpp b/layout/generic/nsHTMLReflowState.cpp
index 0e53900804f..810513f3211 100644
--- a/layout/generic/nsHTMLReflowState.cpp
+++ b/layout/generic/nsHTMLReflowState.cpp
@@ -2069,10 +2069,10 @@ nsHTMLReflowState::InitConstraints(nsPresContext* aPresContext,
       // Exclude inline tables and flex items from the block margin calculations
       if (isBlock &&
           !IsSideCaption(frame, mStyleDisplay) &&
-          mStyleDisplay->mDisplay != NS_STYLE_DISPLAY_INLINE_TABLE
-          && !flexContainerFrame
-          )
+          mStyleDisplay->mDisplay != NS_STYLE_DISPLAY_INLINE_TABLE &&
+          !flexContainerFrame) {
         CalculateBlockSideMargins(availableWidth, mComputedWidth, aFrameType);
+      }
     }
   }
 }
diff --git a/layout/style/test/Makefile.in b/layout/style/test/Makefile.in
index c9bfa7ed457..8ea5a09d9dc 100644
--- a/layout/style/test/Makefile.in
+++ b/layout/style/test/Makefile.in
@@ -99,6 +99,21 @@ MOCHITEST_FILES =	test_acid3_test46.html \
 		test_descriptor_storage.html \
 		test_descriptor_syntax_errors.html \
 		test_dont_use_document_colors.html \
+		file_flexbox_align_self_auto.html \
+		test_flexbox_align_self_auto.html \
+		file_flexbox_child_display_values.xhtml \
+		test_flexbox_child_display_values.html \
+		file_flexbox_flex_grow_and_shrink.html \
+		test_flexbox_flex_grow_and_shrink.html \
+		file_flexbox_flex_shorthand.html \
+		test_flexbox_flex_shorthand.html \
+		file_flexbox_layout.html \
+		test_flexbox_layout.html \
+		flexbox_layout_testcases.js \
+		file_flexbox_order.html \
+		test_flexbox_order.html \
+		file_flexbox_order_table.html \
+		test_flexbox_order_table.html \
 		test_font_face_parser.html \
 		test_font_family_parsing.html \
 		test_font_feature_values_parsing.html \
@@ -200,24 +215,6 @@ MOCHITEST_FILES =	test_acid3_test46.html \
 		viewport_units_iframe.html \
 		$(NULL)
 
-MOCHITEST_FILES +=	\
-		file_flexbox_align_self_auto.html \
-		test_flexbox_align_self_auto.html \
-		file_flexbox_child_display_values.xhtml \
-		test_flexbox_child_display_values.html \
-		file_flexbox_flex_grow_and_shrink.html \
-		test_flexbox_flex_grow_and_shrink.html \
-		file_flexbox_flex_shorthand.html \
-		test_flexbox_flex_shorthand.html \
-		file_flexbox_layout.html \
-		test_flexbox_layout.html \
-		flexbox_layout_testcases.js \
-		file_flexbox_order.html \
-		test_flexbox_order.html \
-		file_flexbox_order_table.html \
-		test_flexbox_order_table.html \
-		$(NULL)
-
 _VISITED_REFTEST_FILES = \
 		$(shell find $(topsrcdir)/layout/reftests/css-visited/ -name '*.html' -o -name '*.xhtml') \
 		$(topsrcdir)/layout/reftests/svg/pseudo-classes-02.svg \