Frameworks/native: Wall Werror in surfaceflinger

Turn on -Wall -Werror in services/surfaceflinger. Fix warnings.

Change-Id: Ifef830300d9d4bc657d8f1257c02bfe8c2b4d9c5
diff --git a/services/surfaceflinger/DisplayHardware/FramebufferSurface.cpp b/services/surfaceflinger/DisplayHardware/FramebufferSurface.cpp
index 086ccf8..342016e 100644
--- a/services/surfaceflinger/DisplayHardware/FramebufferSurface.cpp
+++ b/services/surfaceflinger/DisplayHardware/FramebufferSurface.cpp
@@ -68,7 +68,7 @@
     mConsumer->setDefaultMaxBufferCount(NUM_FRAMEBUFFER_SURFACE_BUFFERS);
 }
 
-status_t FramebufferSurface::beginFrame(bool mustRecompose) {
+status_t FramebufferSurface::beginFrame(bool /* mustRecompose */) {
     return NO_ERROR;
 }