Bug 903543 - eliminate static constructors for SMIL type singletons; r=dholbert

Add MOZ_CONSTEXPR to the constructors to inform the compiler the constructors
can be folded away.  Remove protected/private destructors so that static
destructors don't have to be registered with static constructors.

content/smil/SMILBoolType.h

@@ -40,10 +40,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SMILBoolType()  {}
-  ~SMILBoolType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SMILBoolType() {}
 };
 
 } // namespace mozilla

content/smil/SMILEnumType.h

@@ -41,10 +41,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SMILEnumType()  {}
-  ~SMILEnumType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SMILEnumType() {}
 };
 
 } // namespace mozilla

content/smil/SMILIntegerType.h

@@ -37,7 +37,7 @@ public:
   }
 
 private:
-  SMILIntegerType() {}
+  MOZ_CONSTEXPR SMILIntegerType() {}
 };
 
 } // namespace mozilla

content/smil/SMILStringType.h

@@ -41,10 +41,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SMILStringType()  {}
-  ~SMILStringType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SMILStringType() {}
 };
 
 } // namespace mozilla

content/smil/nsISMILType.h

@@ -6,6 +6,7 @@
 #ifndef NS_ISMILTYPE_H_
 #define NS_ISMILTYPE_H_
 
+#include "mozilla/Attributes.h"
 #include "nscore.h"
 
 class nsSMILValue;
@@ -207,13 +208,6 @@ protected:
                                const nsSMILValue& aEndVal,
                                double aUnitDistance,
                                nsSMILValue& aResult) const = 0;
-
-  /**
-   * Protected destructor, to ensure that no one accidentally deletes an
-   * instance of this class.
-   * (The only instances in existence should be singletons - one per subclass.)
-   */
-  ~nsISMILType() {}
 };
 
 #endif // NS_ISMILTYPE_H_

content/smil/nsSMILCSSValueType.h

@@ -98,10 +98,8 @@ public:
   static bool ValueToString(const nsSMILValue& aValue, nsAString& aString);
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  nsSMILCSSValueType()  {}
-  ~nsSMILCSSValueType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR nsSMILCSSValueType() {}
 };
 
 #endif // NS_SMILCSSVALUETYPE_H_

content/smil/nsSMILFloatType.h

@@ -39,10 +39,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  nsSMILFloatType()  {}
-  ~nsSMILFloatType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR nsSMILFloatType() {}
 };
 
 #endif // NS_SMILFLOATTYPE_H_

content/smil/nsSMILNullType.h

@@ -42,10 +42,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  nsSMILNullType()  {}
-  ~nsSMILNullType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR nsSMILNullType() {}
 };
 
 #endif // NS_SMILNULLTYPE_H_

content/svg/content/src/SVGIntegerPairSMILType.h

@@ -43,10 +43,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SVGIntegerPairSMILType()  {}
-  ~SVGIntegerPairSMILType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SVGIntegerPairSMILType() {}
 };
 
 } // namespace mozilla

content/svg/content/src/SVGLengthListSMILType.h

@@ -91,10 +91,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SVGLengthListSMILType() {}
-  ~SVGLengthListSMILType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SVGLengthListSMILType() {}
 };
 
 } // namespace mozilla

content/svg/content/src/SVGMotionSMILType.h

@@ -71,10 +71,8 @@ public:
                                         float aRotateAngle);
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SVGMotionSMILType()  {}
-  ~SVGMotionSMILType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SVGMotionSMILType() {}
 };
 
 } // namespace mozilla

content/svg/content/src/SVGNumberListSMILType.h

@@ -45,10 +45,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SVGNumberListSMILType() {}
-  ~SVGNumberListSMILType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SVGNumberListSMILType() {}
 };
 
 } // namespace mozilla

content/svg/content/src/SVGNumberPairSMILType.h

@@ -38,10 +38,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SVGNumberPairSMILType()  {}
-  ~SVGNumberPairSMILType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SVGNumberPairSMILType() {}
 };
 
 } // namespace mozilla

content/svg/content/src/SVGOrientSMILType.h

@@ -58,10 +58,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SVGOrientSMILType()  {}
-  ~SVGOrientSMILType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SVGOrientSMILType() {}
 };
 
 } // namespace mozilla

content/svg/content/src/SVGPathSegListSMILType.h

@@ -49,10 +49,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SVGPathSegListSMILType() {}
-  ~SVGPathSegListSMILType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SVGPathSegListSMILType() {}
 };
 
 } // namespace mozilla

content/svg/content/src/SVGPointListSMILType.h

@@ -45,10 +45,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SVGPointListSMILType() {}
-  ~SVGPointListSMILType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SVGPointListSMILType() {}
 };
 
 } // namespace mozilla

content/svg/content/src/SVGTransformListSMILType.h

@@ -121,10 +121,8 @@ public:
 
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SVGTransformListSMILType() {}
-  ~SVGTransformListSMILType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SVGTransformListSMILType() {}
 };
 
 } // end namespace mozilla

content/svg/content/src/SVGViewBoxSMILType.h

@@ -38,10 +38,8 @@ protected:
                                nsSMILValue& aResult) const MOZ_OVERRIDE;
 
 private:
-  // Private constructor & destructor: prevent instances beyond my singleton,
-  // and prevent others from deleting my singleton.
-  SVGViewBoxSMILType()  {}
-  ~SVGViewBoxSMILType() {}
+  // Private constructor: prevent instances beyond my singleton.
+  MOZ_CONSTEXPR SVGViewBoxSMILType() {}
 };
 
 } // namespace mozilla