Silence a memory leak warning from the static analyzer

The analyzer assumes that the given `put` operation may fail. This
shouldn't be the case, so mark it with a LOG_ALWAYS_FATAL_IF. Doing so
silences a warning about potential memory leaks originating from
TessellationCache::getRoundRect.

Bug: 27101951
Test: mma. Warning is gone.
Change-Id: I3adeacd6c2c9c03caecd989e2a1267c51e8ef905
diff --git a/libs/hwui/TessellationCache.cpp b/libs/hwui/TessellationCache.cpp
index d9e8116..4ea440d 100644
--- a/libs/hwui/TessellationCache.cpp
+++ b/libs/hwui/TessellationCache.cpp
@@ -416,7 +416,9 @@
             mProcessor = new TessellationProcessor(Caches::getInstance());
         }
         mProcessor->add(task);
-        mCache.put(entry, buffer);
+        bool inserted = mCache.put(entry, buffer);
+        // Note to the static analyzer that this insert should always succeed.
+        LOG_ALWAYS_FATAL_IF(!inserted, "buffers shouldn't spontaneously appear in the cache");
     }
     return buffer;
 }