Fix bug where dirty messages for allocations attached to programVertex objects could be lost.

libs/rs/rsContext.cpp

@@ -438,6 +438,7 @@ void Context::setVertex(ProgramVertex *pv)
     } else {
         mVertex.set(pv);
     }
+    mVertex->forceDirty();
 }
 
 void Context::assignName(ObjectBase *obj, const char *name, uint32_t len)

libs/rs/rsProgram.h

@@ -44,6 +44,10 @@ protected:
     ObjectBaseRef<Allocation> mConstants;
 
     mutable bool mDirty;
+
+
+public:
+    void forceDirty() {mDirty = true;}
 };