Add AHB and Pixel- Formats for R8

Add AHARDWAREBUFFER_FORMAT_R8_UNORM and PIXEL_FORMAT_R_8. These will be
used for an alpha 8 buffer representing the screen decorations.

Enum value matches AIDL R_8 in
I6f6b7f22e76609151a413ca6a6dbf55bd91911dd.

Bug: 193170859
Test: make
Change-Id: I4846327b29736ee811672801a683deb287342a8e
diff --git a/services/surfaceflinger/BufferLayer.cpp b/services/surfaceflinger/BufferLayer.cpp
index 494b61c..64ddd68 100644
--- a/services/surfaceflinger/BufferLayer.cpp
+++ b/services/surfaceflinger/BufferLayer.cpp
@@ -564,15 +564,16 @@
 // hardware.h, instead of using hard-coded values here.
 #define HARDWARE_IS_DEVICE_FORMAT(f) ((f) >= 0x100 && (f) <= 0x1FF)
 
-bool BufferLayer::getOpacityForFormat(uint32_t format) {
+bool BufferLayer::getOpacityForFormat(PixelFormat format) {
     if (HARDWARE_IS_DEVICE_FORMAT(format)) {
         return true;
     }
     switch (format) {
-        case HAL_PIXEL_FORMAT_RGBA_8888:
-        case HAL_PIXEL_FORMAT_BGRA_8888:
-        case HAL_PIXEL_FORMAT_RGBA_FP16:
-        case HAL_PIXEL_FORMAT_RGBA_1010102:
+        case PIXEL_FORMAT_RGBA_8888:
+        case PIXEL_FORMAT_BGRA_8888:
+        case PIXEL_FORMAT_RGBA_FP16:
+        case PIXEL_FORMAT_RGBA_1010102:
+        case PIXEL_FORMAT_R_8:
             return false;
     }
     // in all other case, we have no blending (also for unknown formats)
diff --git a/services/surfaceflinger/BufferLayer.h b/services/surfaceflinger/BufferLayer.h
index a4c21f4..34d11ac 100644
--- a/services/surfaceflinger/BufferLayer.h
+++ b/services/surfaceflinger/BufferLayer.h
@@ -153,7 +153,7 @@
     bool onPreComposition(nsecs_t) override;
     void preparePerFrameCompositionState() override;
 
-    static bool getOpacityForFormat(uint32_t format);
+    static bool getOpacityForFormat(PixelFormat format);
 
     // from graphics API
     const uint32_t mTextureName;