Moved brightness from Lights to SF.

Test: manual.
      Check that brightness works.
Fixes: 111435292

Change-Id: I96dfdf0ad5d16fdb03e575cbe05ad4e1dbc8ee36
diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.h b/services/surfaceflinger/DisplayHardware/HWComposer.h
index ca59a26..de863b8 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.h
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.h
@@ -140,6 +140,9 @@
                                                uint64_t timestamp,
                                                DisplayedFrameStats* outStats) = 0;
 
+    // Sets the brightness of a display.
+    virtual status_t setDisplayBrightness(DisplayId displayId, float brightness) = 0;
+
     // Events handling ---------------------------------------------------------
 
     // Returns stable display ID (and display name on connection of new or previously disconnected
@@ -271,6 +274,7 @@
                                               uint8_t componentMask, uint64_t maxFrames) override;
     status_t getDisplayedContentSample(DisplayId displayId, uint64_t maxFrames, uint64_t timestamp,
                                        DisplayedFrameStats* outStats) override;
+    status_t setDisplayBrightness(DisplayId displayId, float brightness) override;
 
     // Events handling ---------------------------------------------------------