Orphan ProcXfermode, with an eye towards removing it

tests/XfermodeTest.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkColor.h"
 #include "SkXfermode.h"
 #include "Test.h"
 
-static SkPMColor bogusXfermodeProc(SkPMColor src, SkPMColor dst) {
-    return 42;
-}
-
 #define ILLEGAL_MODE    ((SkXfermode::Mode)-1)
 
 static void test_asMode(skiatest::Reporter* reporter) {
     for (int mode = 0; mode <= SkXfermode::kLastMode; mode++) {
         SkXfermode* xfer = SkXfermode::Create((SkXfermode::Mode) mode);
 
         SkXfermode::Mode reportedMode = ILLEGAL_MODE;
         REPORTER_ASSERT(reporter, reportedMode != mode);
 
         // test IsMode
         REPORTER_ASSERT(reporter, SkXfermode::AsMode(xfer, &reportedMode));
         REPORTER_ASSERT(reporter, reportedMode == mode);
 
         // repeat that test, but with asMode instead
         if (xfer) {
             reportedMode = (SkXfermode::Mode) -1;
             REPORTER_ASSERT(reporter, xfer->asMode(&reportedMode));
             REPORTER_ASSERT(reporter, reportedMode == mode);
             xfer->unref();
         } else {
             REPORTER_ASSERT(reporter, SkXfermode::kSrcOver_Mode == mode);
         }
     }
-
-    SkXfermode* bogusXfer = SkProcXfermode::Create(bogusXfermodeProc);
-    SkXfermode::Mode reportedMode = ILLEGAL_MODE;
-    REPORTER_ASSERT(reporter, !bogusXfer->asMode(&reportedMode));
-    REPORTER_ASSERT(reporter, reportedMode == ILLEGAL_MODE);
-    REPORTER_ASSERT(reporter, !SkXfermode::AsMode(bogusXfer, &reportedMode));
-    REPORTER_ASSERT(reporter, reportedMode == ILLEGAL_MODE);
-    bogusXfer->unref();
 }
 
 static void test_IsMode(skiatest::Reporter* reporter) {
     REPORTER_ASSERT(reporter, SkXfermode::IsMode(NULL,
                                                  SkXfermode::kSrcOver_Mode));
 
     for (int i = 0; i <= SkXfermode::kLastMode; ++i) {
         SkXfermode::Mode mode = (SkXfermode::Mode)i;
 
         SkXfermode* xfer = SkXfermode::Create(mode);
         REPORTER_ASSERT(reporter, SkXfermode::IsMode(xfer, mode));
         SkSafeUnref(xfer);
 
         if (SkXfermode::kSrcOver_Mode != mode) {
             REPORTER_ASSERT(reporter, !SkXfermode::IsMode(NULL, mode));
         }
     }
 }
 
 DEF_TEST(Xfermode, reporter) {
     test_asMode(reporter);
     test_IsMode(reporter);
 }