avm2: Implement `Matrix3D.prependScale`

core/src/avm2/globals/flash/geom/Matrix3D.as

@@ -371,6 +371,12 @@ package flash.geom {
 			this._rawData[15] = m141 * m214 + m142 * m224 + m143 * m234 + m144 * m244;
 		}
 
+		public function prependScale(xScale:Number, yScale:Number, zScale:Number):void {
+			var m = new Matrix3D();
+			m.appendScale(xScale, yScale, zScale);
+			this.prepend(m);
+		}
+
 		public function copyFrom(other:Matrix3D):void {
 			// This makes a copy of other.rawData
 			this._rawData = other.rawData;

tests/tests/swfs/avm2/matrix3d/Test.as

@@ -149,6 +149,9 @@
 			newMat.prependRotation(90, Vector3D.X_AXIS);
 			trace("After prependRotation: " + newMat.rawData);
 
+			newMat.prependScale(1, 2, 3);
+			trace("After prependScale: " + newMat.rawData);
+
 
 			trace("// copyColumnFrom tests");
 			var columnMatrix:Matrix3D = new Matrix3D(Vector.<Number>([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]));

tests/tests/swfs/avm2/matrix3d/output.txt

@@ -48,6 +48,7 @@ Row 4: ArgumentError: Error #2004: One of the parameters is invalid.
 Copy from row 4: ArgumentError: Error #2004: One of the parameters is invalid.
 After row copies: 100,500,900,1300,200,600,1000,1400,300,700,1100,1500,400,800,1200,1600
 After prependRotation: 100,500,900,1300,300,700,1100,1500,-200,-600,-1000,-1400,400,800,1200,1600
+After prependScale: 100,500,900,1300,600,1400,2200,3000,-600,-1800,-3000,-4200,400,800,1200,1600
 // copyColumnFrom tests
 Matrix raw data: 3,4,5,6,0,0,0,0,0,0,0,0,0,0,0,0
 Matrix raw data: 3,4,5,6,3,4,5,6,0,0,0,0,0,0,0,0