SF: pass Color as float to HWC

In HWC3 Color is represented as a float [0.0 - 1.0] to be consistent
across the stack. SF passes the color as float and it gets translated
back to uint8_t for HWC2.

Bug: 207139550
Test: atest SurfaceFlinger_test
Change-Id: I83867eed70bd3baa3292c9cc099d891ba9cc6183
diff --git a/services/surfaceflinger/DisplayHardware/HWC2.cpp b/services/surfaceflinger/DisplayHardware/HWC2.cpp
index 22479d8..eadbfc7 100644
--- a/services/surfaceflinger/DisplayHardware/HWC2.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWC2.cpp
@@ -37,6 +37,7 @@
 #include <iterator>
 #include <set>
 
+using aidl::android::hardware::graphics::composer3::Color;
 using aidl::android::hardware::graphics::composer3::Composition;
 using aidl::android::hardware::graphics::composer3::DisplayCapability;