clean-up/simplify all dump() APIs

remove the scratch buffer parameter and use
String8::appendFormat() instead.

Change-Id: Ib96c91617c8e7292de87433d15cf6232b7d591b0
diff --git a/services/surfaceflinger/DisplayHardware/FramebufferSurface.h b/services/surfaceflinger/DisplayHardware/FramebufferSurface.h
index 2fde789..c86e9ae 100644
--- a/services/surfaceflinger/DisplayHardware/FramebufferSurface.h
+++ b/services/surfaceflinger/DisplayHardware/FramebufferSurface.h
@@ -55,8 +55,7 @@
     virtual void onFrameAvailable();
     virtual void freeBufferLocked(int slotIndex);
 
-    virtual void dumpLocked(String8& result, const char* prefix,
-            char* buffer, size_t SIZE) const;
+    virtual void dumpLocked(String8& result, const char* prefix) const;
 
     // nextBuffer waits for and then latches the next buffer from the
     // BufferQueue and releases the previously latched buffer to the