add allowImageFilter() so a device can allow/disallow filters
(esp. for printing)



git-svn-id: http://skia.googlecode.com/svn/trunk@2981 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/device/xps/SkXPSDevice.cpp b/src/device/xps/SkXPSDevice.cpp
index a32eb26..e2e23fa 100644
--- a/src/device/xps/SkXPSDevice.cpp
+++ b/src/device/xps/SkXPSDevice.cpp
@@ -2384,6 +2384,7 @@
                                                 bool isOpaque,
                                                 Usage usage) {
     if (SkDevice::kGeneral_Usage == usage) {
+        return NULL;
         SK_CRASH();
         //To what stream do we write?
         //SkXPSDevice* dev = new SkXPSDevice(this);
@@ -2409,3 +2410,8 @@
     HRVM(this->fXpsFactory->CreateCanvas(&this->fCurrentXpsCanvas),
          "Could not create canvas for layer.");
 }
+
+bool SkXPSDevice::allowImageFilter(SkImageFilter*) {
+    return false;
+}
+