SkDiscardablePixelRef returns correct indexed color on relock.

src/lazy/SkDiscardablePixelRef.cpp

Index: src/lazy/SkDiscardablePixelRef.cpp
diff --git a/src/lazy/SkDiscardablePixelRef.cpp b/src/lazy/SkDiscardablePixelRef.cpp
index f0d7affdc8fe985a62629e784cff84d9e7e361b9..ce38a4a877b9f2cad2c645b3ec66b9309aba95a6 100644
--- a/src/lazy/SkDiscardablePixelRef.cpp
+++ b/src/lazy/SkDiscardablePixelRef.cpp
@@ -40,7 +40,7 @@ bool SkDiscardablePixelRef::onNewLockPixels(LockRec* rec) {
     if (fDiscardableMemory != NULL) {
         if (fDiscardableMemory->lock()) {
             rec->fPixels = fDiscardableMemory->data();
-            rec->fColorTable = NULL;
+            rec->fColorTable = fCTable.get();
             rec->fRowBytes = fRowBytes;
             return true;
         }