diff --git a/mozilla/content/html/style/src/nsCSSDeclaration.cpp b/mozilla/content/html/style/src/nsCSSDeclaration.cpp
index 499f2e7da74..bd4f6f54489 100644
--- a/mozilla/content/html/style/src/nsCSSDeclaration.cpp
+++ b/mozilla/content/html/style/src/nsCSSDeclaration.cpp
@@ -5458,7 +5458,7 @@ nsCSSDeclaration::TryBorderShorthand(nsAString & aString, PRUint32 aPropertiesSe
                                      PRInt32 aBorderRightStyle,
                                      PRInt32 aBorderRightColor)
 {
-  PRBool border = PR_FALSE, isImportant;
+  PRBool border = PR_FALSE, isImportant = PR_FALSE;
   // 0 means not in the mOrder array; otherwise it's index+1
   if (B_BORDER == aPropertiesSet
       && AllPropertiesSameValue(aBorderTopWidth, aBorderBottomWidth,
diff --git a/mozilla/content/html/style/src/nsCSSStruct.cpp b/mozilla/content/html/style/src/nsCSSStruct.cpp
index 499f2e7da74..bd4f6f54489 100644
--- a/mozilla/content/html/style/src/nsCSSStruct.cpp
+++ b/mozilla/content/html/style/src/nsCSSStruct.cpp
@@ -5458,7 +5458,7 @@ nsCSSDeclaration::TryBorderShorthand(nsAString & aString, PRUint32 aPropertiesSe
                                      PRInt32 aBorderRightStyle,
                                      PRInt32 aBorderRightColor)
 {
-  PRBool border = PR_FALSE, isImportant;
+  PRBool border = PR_FALSE, isImportant = PR_FALSE;
   // 0 means not in the mOrder array; otherwise it's index+1
   if (B_BORDER == aPropertiesSet
       && AllPropertiesSameValue(aBorderTopWidth, aBorderBottomWidth,
diff --git a/mozilla/layout/style/nsCSSDeclaration.cpp b/mozilla/layout/style/nsCSSDeclaration.cpp
index 499f2e7da74..bd4f6f54489 100644
--- a/mozilla/layout/style/nsCSSDeclaration.cpp
+++ b/mozilla/layout/style/nsCSSDeclaration.cpp
@@ -5458,7 +5458,7 @@ nsCSSDeclaration::TryBorderShorthand(nsAString & aString, PRUint32 aPropertiesSe
                                      PRInt32 aBorderRightStyle,
                                      PRInt32 aBorderRightColor)
 {
-  PRBool border = PR_FALSE, isImportant;
+  PRBool border = PR_FALSE, isImportant = PR_FALSE;
   // 0 means not in the mOrder array; otherwise it's index+1
   if (B_BORDER == aPropertiesSet
       && AllPropertiesSameValue(aBorderTopWidth, aBorderBottomWidth,
diff --git a/mozilla/layout/style/nsCSSStruct.cpp b/mozilla/layout/style/nsCSSStruct.cpp
index 499f2e7da74..bd4f6f54489 100644
--- a/mozilla/layout/style/nsCSSStruct.cpp
+++ b/mozilla/layout/style/nsCSSStruct.cpp
@@ -5458,7 +5458,7 @@ nsCSSDeclaration::TryBorderShorthand(nsAString & aString, PRUint32 aPropertiesSe
                                      PRInt32 aBorderRightStyle,
                                      PRInt32 aBorderRightColor)
 {
-  PRBool border = PR_FALSE, isImportant;
+  PRBool border = PR_FALSE, isImportant = PR_FALSE;
   // 0 means not in the mOrder array; otherwise it's index+1
   if (B_BORDER == aPropertiesSet
       && AllPropertiesSameValue(aBorderTopWidth, aBorderBottomWidth,