sdm: add solid fill setter display API support

1. Create 2 layers in HWC of types HWC_FRAMEBUFFER and
   HWC_FRAMEWORK_TARGET once receiving QDCM tool request.
2. Add new Layer flags and bg_color properties to SDM core Layer
   structure to indicate this Layer is solid fill without
   input_buffer associated.
3. Use HWCSession::Prepare<>/Set<> to render solid fill
   layers.
4. Primary HWFB will detect solid_fill Layer flags and populate
   mdp_input_layer.flags with MDP_LAYER_SOLID_FILL to make use of
   MDP hardware solid fill feature.

Change-Id: I18d0bf0712e9dd36c78ce2cb025abf6c758ce453
diff --git a/sdm/libs/hwc/hwc_debugger.h b/sdm/libs/hwc/hwc_debugger.h
index 9fedb80..46f6a25 100644
--- a/sdm/libs/hwc/hwc_debugger.h
+++ b/sdm/libs/hwc/hwc_debugger.h
@@ -63,6 +63,7 @@
   static void DebugDriverConfig(bool enable, int verbose_level);
   static void DebugRotator(bool enable, int verbose_level);
   static void DebugQdcm(bool enable, int verbose_level);
+  static int  GetIdleTimeoutMs();
 
   virtual void Error(DebugTag tag, const char *format, ...);
   virtual void Warning(DebugTag tag, const char *format, ...);