Apply SDR scaling to solid color quads in Skia renderer

Bug: chromium:985500

Change-Id: I0f2c00ac5aac0a939d87a5c0d1e53fd6f53d8313
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1917621Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Reviewed-by: kylechar <kylechar@chromium.org>
Commit-Queue: Brian Osman <brianosman@google.com>
Cr-Commit-Position: refs/heads/master@{#715685}

components/viz/service/BUILD.gn

@@ -206,6 +206,7 @@ viz_component("service") {
     "//media/capture:capture_lib",
     "//media/mojo/services",
     "//services/viz/privileged/mojom",
+    "//skia:skcms",
     "//ui/display/types",
   ]
 

components/viz/service/display/skia_renderer.cc

@@ -54,6 +54,7 @@
 #include "third_party/skia/include/effects/SkOverdrawColorFilter.h"
 #include "third_party/skia/include/effects/SkShaderMaskFilter.h"
 #include "third_party/skia/include/gpu/GrBackendSurface.h"
+#include "third_party/skia/include/third_party/skcms/skcms.h"
 #include "third_party/skia/src/core/SkColorFilterPriv.h"
 #include "ui/gfx/color_transform.h"
 #include "ui/gfx/geometry/axis_transform2d.h"
@@ -1642,9 +1643,26 @@ void SkiaRenderer::DrawColoredQuad(SkColor color,
   color = SkColorSetA(color, params->opacity * SkColorGetA(color));
   const SkPoint* draw_region =
       params->draw_region.has_value() ? params->draw_region->points : nullptr;
+
+  SkColor4f color4f = SkColor4f::FromColor(color);
+  float sdr_white_level = current_frame()->sdr_white_level;
+  if (sdr_white_level != gfx::ColorSpace::kDefaultSDRWhiteLevel) {
+    // SkColor is always sRGB. Use skcms to linearize, scale, and re-encode
+    const float scale_factor =
+        sdr_white_level / gfx::ColorSpace::kDefaultSDRWhiteLevel;
+    const auto* srgb_to_linear = skcms_sRGB_TransferFunction();
+    const auto* linear_to_srgb = skcms_sRGB_Inverse_TransferFunction();
+
+    for (int c = 0; c < 3; ++c) {
+      color4f[c] = skcms_TransferFunction_eval(
+          linear_to_srgb, scale_factor * skcms_TransferFunction_eval(
+                                             srgb_to_linear, color4f[c]));
+    }
+  }
+
   current_canvas_->experimental_DrawEdgeAAQuad(
       gfx::RectFToSkRect(params->visible_rect), draw_region,
-      static_cast<SkCanvas::QuadAAFlags>(params->aa_flags), color,
+      static_cast<SkCanvas::QuadAAFlags>(params->aa_flags), color4f,
       params->blend_mode);
 }