Make Matrix#orNullIfIdentity() private too, and fix error introduced by previous commit.

src/basic/Matrix.js

@@ -486,6 +486,10 @@ var Matrix = Base.extend(/** @lends Matrix# */{
         return new Matrix(this._a, this._c, this._b, this._d, 0, 0);
     },
 
+    _orNullIfIdentity: function() {
+        return this.isIdentity() ? null : this;
+    },
+
     /**
      * @return {Boolean} whether this transform is the identity transform
      */
@@ -494,10 +498,6 @@ var Matrix = Base.extend(/** @lends Matrix# */{
                 && this._tx === 0 && this._ty === 0;
     },
 
-    orNullIfIdentity: function() {
-        return this.isIdentity() ? null : this;
-    },
-
     /**
      * Returns whether the transform is invertible. A transform is not
      * invertible if the determinant is 0 or any value is non-finite or NaN.

src/item/Item.js

@@ -879,9 +879,9 @@ var Item = Base.extend(Emitter, /** @lends Item# */{
         // See if we can cache these bounds. We only cache the bounds
         // transformed with the internally stored _matrix, (the default if no
         // matrix is passed).
-        matrix = matrix && matrix.orNullIfIdentity();
+        matrix = matrix && matrix._orNullIfIdentity();
         // Do not transform by the internal matrix if there is a internalGetter.
-        var _matrix = internalGetter ? null : this._matrix.orNullIfIdentity(),
+        var _matrix = internalGetter ? null : this._matrix._orNullIfIdentity(),
             cache = (!matrix || matrix.equals(_matrix)) && getter;
         // NOTE: This needs to happen before returning cached values, since even
         // then, _boundsCache needs to be kept up-to-date.

src/path/Path.js

@@ -2770,7 +2770,7 @@ statics: {
             return Path.getBounds(segments, closed, style, matrix);
         var length = segments.length - (closed ? 0 : 1),
             radius = style.getStrokeWidth() / 2,
-            padding = Path._getPenPadding(radius, matrix),
+            padding = Path._getStrokePadding(radius, matrix),
             bounds = Path.getBounds(segments, closed, style, matrix, padding),
             join = style.getStrokeJoin(),
             cap = style.getStrokeCap(),

src/path/PathItem.js

@@ -69,9 +69,9 @@ var PathItem = Item.extend(/** @lends PathItem# */{
         // NOTE: The hidden argument _matrix is used internally to override the
         // passed path's transformation matrix.
         var self = this === path || !path, // self-intersections?
-            matrix1 = this._matrix.orNullIfIdentity(),
+            matrix1 = this._matrix._orNullIfIdentity(),
             matrix2 = self ? matrix1
-                : (_matrix || path._matrix).orNullIfIdentity();
+                : (_matrix || path._matrix)._orNullIfIdentity();
         // First check the bounds of the two paths. If they don't intersect,
         // we don't need to iterate through their curves.
         if (!self && !this.getBounds(matrix1).touches(path.getBounds(matrix2)))