color: Clarify default behaviors

ui/gfx/color_transform_unittest.cc

Index: ui/gfx/color_transform_unittest.cc
diff --git a/ui/gfx/color_transform_unittest.cc b/ui/gfx/color_transform_unittest.cc
index 8393a39fa79df98377ecdbd84d1a15f575e193d0..9633af64b651acd7b693f7afbbc0b4f9722d329b 100644
--- a/ui/gfx/color_transform_unittest.cc
+++ b/ui/gfx/color_transform_unittest.cc
@@ -99,8 +99,8 @@ TEST(SimpleColorSpace, SRGBFromICCAndNotICC) {
   std::unique_ptr<ColorTransform> toxyzd50_fromicc(
       ColorTransform::NewColorTransform(
           srgb_fromicc, xyzd50, ColorTransform::Intent::INTENT_ABSOLUTE));
-  // This will have 1 step, namely, the QCMS transform.
-  EXPECT_EQ(toxyzd50_fromicc->NumberOfStepsForTesting(), 1u);
+  // This will be converted to a transfer function and then linear transform.
+  EXPECT_EQ(toxyzd50_fromicc->NumberOfStepsForTesting(), 2u);
   toxyzd50_fromicc->Transform(&value_fromicc, 1);
 
   std::unique_ptr<ColorTransform> toxyzd50_default(
@@ -200,23 +200,31 @@ TEST(SimpleColorSpace, UnknownToSRGB) {
   std::unique_ptr<ColorTransform> t(ColorTransform::NewColorTransform(
       unknown, sRGB, ColorTransform::Intent::INTENT_PERCEPTUAL));
 
-  ColorTransform::TriStim tmp(16.0f / 255.0f, 0.5f, 0.5f);
+  EXPECT_EQ(t->NumberOfStepsForTesting(), 0u);
+
+  ColorTransform::TriStim input;
+  ColorTransform::TriStim tmp;
+  input = ColorTransform::TriStim(16.0f / 255.0f, 0.5f, 0.5f);
+  tmp = input;
   t->Transform(&tmp, 1);
-  EXPECT_NEAR(tmp.x(), 0.0f, 0.001f);
-  EXPECT_NEAR(tmp.y(), 0.0f, 0.001f);
-  EXPECT_NEAR(tmp.z(), 0.0f, 0.001f);
+  EXPECT_NEAR(tmp.x(), input.x(), 0.001f);
+  EXPECT_NEAR(tmp.y(), input.y(), 0.001f);
+  EXPECT_NEAR(tmp.z(), input.z(), 0.001f);
 
-  tmp = ColorTransform::TriStim(235.0f / 255.0f, 0.5f, 0.5f);
+  input = ColorTransform::TriStim(235.0f / 255.0f, 0.5f, 0.5f);
+  tmp = input;
   t->Transform(&tmp, 1);
-  EXPECT_NEAR(tmp.x(), 1.0f, 0.001f);
-  EXPECT_NEAR(tmp.y(), 1.0f, 0.001f);
-  EXPECT_NEAR(tmp.z(), 1.0f, 0.001f);
+  EXPECT_NEAR(tmp.x(), input.x(), 0.001f);
+  EXPECT_NEAR(tmp.y(), input.y(), 0.001f);
+  EXPECT_NEAR(tmp.z(), input.z(), 0.001f);
 
   // Test a blue color
-  tmp = ColorTransform::TriStim(128.0f / 255.0f, 240.0f / 255.0f, 0.5f);
+  input = ColorTransform::TriStim(128.0f / 255.0f, 240.0f / 255.0f, 0.5f);
+  tmp = input;
   t->Transform(&tmp, 1);
-  EXPECT_GT(tmp.z(), tmp.x());
-  EXPECT_GT(tmp.z(), tmp.y());
+  EXPECT_NEAR(tmp.x(), input.x(), 0.001f);
+  EXPECT_NEAR(tmp.y(), input.y(), 0.001f);
+  EXPECT_NEAR(tmp.z(), input.z(), 0.001f);
 }
 
 class TransferTest : public testing::TestWithParam<ColorSpace::TransferID> {};