more clean-up in preparation of bigger changes

the most important change here is the renaming of
ISurfaceFlingerClient to ISurfaceComposerClient

Change-Id: I94e18b0417f50e06f21377446639c61f65f959b3
diff --git a/include/private/surfaceflinger/SharedBufferStack.h b/include/private/surfaceflinger/SharedBufferStack.h
index b859e78..dcce25e 100644
--- a/include/private/surfaceflinger/SharedBufferStack.h
+++ b/include/private/surfaceflinger/SharedBufferStack.h
@@ -136,9 +136,7 @@
 public:
     SharedClient();
     ~SharedClient();
-
     status_t validate(size_t token) const;
-    uint32_t getIdentity(size_t token) const;
 
 private:
     friend class SharedBufferBase;
@@ -160,6 +158,7 @@
             int32_t identity);
     ~SharedBufferBase();
     status_t getStatus() const;
+    int32_t getIdentity() const;
     size_t getFrontBuffer() const;
     String8 dump(char const* prefix) const;