guard references to SkColorTable

Bug: skia:6828
Change-Id: I0c8c78e70b118f51cb59dc45675e4ddcd4776108
Reviewed-on: https://skia-review.googlesource.com/24260
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Leon Scroggins <scroggo@google.com>
diff --git a/src/core/SkBitmapCache.cpp b/src/core/SkBitmapCache.cpp
index 50553a0..b876764 100644
--- a/src/core/SkBitmapCache.cpp
+++ b/src/core/SkBitmapCache.cpp
@@ -225,8 +225,7 @@
             SkASSERT(fDM->data());
         }
 
-        bitmap->installPixels(fInfo, fDM ? fDM->data() : fMalloc, fRowBytes, nullptr,
-                              ReleaseProc, this);
+        bitmap->installPixels(fInfo, fDM ? fDM->data() : fMalloc, fRowBytes, ReleaseProc, this);
         SkBitmapCache_setImmutableWithID(bitmap->pixelRef(), fPrUniqueID);
 
         REC_TRACE(" Rec: [%d] install new pr\n", fPrUniqueID);