Tracing swap chain format of overlays with |swap_chain_format_|

Currently, we have three overlay formats: YUV, BGRA, RGB10A2. Previously,
we trace swap chain format with |is_yuv_swapchain_|, which can't provide
accurate information in current situation.

In this CL, we use a member variable |swap_chain_format_| to trace swap
chain format in use.

Bug: 1062184
Change-Id: I0d26564043f097afc0d1ef769c3854ee91a3462f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2336215
Commit-Queue: Richard Li <richard.li@intel.com>
Reviewed-by: Sunny Sachanandani <sunnyps@chromium.org>
Cr-Commit-Position: refs/heads/master@{#796701}

ui/gl/direct_composition_surface_win.cc

@@ -431,7 +431,7 @@ bool DirectCompositionSurfaceWin::IsDecodeSwapChainSupported() {
   if (base::FeatureList::IsEnabled(
           features::kDirectCompositionUseNV12DecodeSwapChain)) {
     UpdateOverlaySupport();
-    return GetOverlayFormatUsed() == DXGI_FORMAT_NV12;
+    return GetOverlayFormatUsedForSDR() == DXGI_FORMAT_NV12;
   }
   return false;
 }
@@ -490,7 +490,7 @@ gfx::Size DirectCompositionSurfaceWin::GetOverlayMonitorSize() {
 }
 
 // static
-DXGI_FORMAT DirectCompositionSurfaceWin::GetOverlayFormatUsed() {
+DXGI_FORMAT DirectCompositionSurfaceWin::GetOverlayFormatUsedForSDR() {
   return g_overlay_format_used;
 }
 
@@ -516,7 +516,7 @@ void DirectCompositionSurfaceWin::SetOverlayFormatUsedForTesting(
   DCHECK(format == DXGI_FORMAT_NV12 || format == DXGI_FORMAT_YUY2);
   UpdateOverlaySupport();
   g_overlay_format_used = format;
-  DCHECK_EQ(format, GetOverlayFormatUsed());
+  DCHECK_EQ(format, GetOverlayFormatUsedForSDR());
 }
 
 // static

ui/gl/direct_composition_surface_win.h

@@ -72,7 +72,7 @@ class GL_EXPORT DirectCompositionSurfaceWin : public GLSurfaceEGL,
   static bool AreScaledOverlaysSupported();
 
   // Returns preferred overlay format set when detecting overlay support.
-  static DXGI_FORMAT GetOverlayFormatUsed();
+  static DXGI_FORMAT GetOverlayFormatUsedForSDR();
 
   // Returns monitor size.
   static gfx::Size GetOverlayMonitorSize();

ui/gl/swap_chain_presenter.h

@@ -102,15 +102,15 @@ class SwapChainPresenter : public base::PowerObserver {
   // |use_yuv_swap_chain| is true, or BGRA otherwise.  Sets flags based on
   // |protected_video_type|. Returns true on success.
   bool ReallocateSwapChain(const gfx::Size& swap_chain_size,
-                           bool use_yuv_swap_chain,
+                           DXGI_FORMAT swap_chain_format,
                            gfx::ProtectedVideoType protected_video_type,
                            bool z_order,
                            bool content_is_hdr);
 
-  // Returns true if YUV swap chain should be preferred over BGRA swap chain.
+  // Returns DXGI format that swap chain uses.
   // This changes over time based on stats recorded in |presentation_history|.
-  bool ShouldUseYUVSwapChain(gfx::ProtectedVideoType protected_video_type,
-                             bool content_is_hdr);
+  DXGI_FORMAT GetSwapChainFormat(gfx::ProtectedVideoType protected_video_type,
+                                 bool content_is_hdr);
 
   // Perform a blit using video processor from given input texture to swap chain
   // backbuffer. |input_texture| is the input texture (array), and |input_level|
@@ -172,8 +172,8 @@ class SwapChainPresenter : public base::PowerObserver {
   // Current size of swap chain.
   gfx::Size swap_chain_size_;
 
-  // Whether the current swap chain is using the preferred YUV format.
-  bool is_yuv_swapchain_ = false;
+  // Current swap chain format.
+  DXGI_FORMAT swap_chain_format_;
 
   // Whether the swap chain was reallocated, and next present will be the first.
   bool first_present_ = false;