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/image/SkImage_Gpu.cpp b/src/image/SkImage_Gpu.cpp
index fa507fe..5dd7943 100644
--- a/src/image/SkImage_Gpu.cpp
+++ b/src/image/SkImage_Gpu.cpp
@@ -680,8 +680,7 @@
     SkAutoPixmapStorage pixmap;
     SkImageInfo info;
     size_t pixelSize = 0;
-    if (!isScaled && this->peekPixels(&pixmap) && !pixmap.ctable() &&
-        pixmap.info().colorType() == dstColorType) {
+    if (!isScaled && this->peekPixels(&pixmap) && pixmap.info().colorType() == dstColorType) {
         info = pixmap.info();
         pixelSize = SkAlign8(pixmap.getSafeSize());
         if (!dstColorSpace) {
@@ -723,7 +722,6 @@
                     return 0;
                 }
             }
-            SkASSERT(!decodePixmap.ctable());
 
             if (decodeInfo.colorType() != info.colorType()) {
                 pixmap.alloc(info);