Revert of ensure that we call onUnlock only when we onLock succeeded

src/core/SkPixelRef.cpp

Index: src/core/SkPixelRef.cpp
diff --git a/src/core/SkPixelRef.cpp b/src/core/SkPixelRef.cpp
index 740d269a27a339065b4a91c9f8fa8fbb4d80ca94..b5daf0b57a90ca0321babf11c37da2eef05fab93 100644
--- a/src/core/SkPixelRef.cpp
+++ b/src/core/SkPixelRef.cpp
@@ -178,10 +178,6 @@
 
         if (1 == ++fLockCount) {
             fPixels = this->onLockPixels(&fColorTable);
-            // If onLockPixels failed, it will return NULL
-            if (NULL == fPixels) {
-                fColorTable = NULL;
-            }
         }
     }
 }
@@ -194,14 +190,9 @@
 
         SkASSERT(fLockCount > 0);
         if (0 == --fLockCount) {
-            // don't call onUnlockPixels unless onLockPixels succeeded
-            if (fPixels) {
-                this->onUnlockPixels();
-                fPixels = NULL;
-                fColorTable = NULL;
-            } else {
-                SkASSERT(NULL == fColorTable);
-            }
+            this->onUnlockPixels();
+            fPixels = NULL;
+            fColorTable = NULL;
         }
     }
 }