Remove enabled flag high_contrast_text_luminance

The flag was relased in 24 Q3. It has been enabled more than 6 month.

NO_IFTTT=New IFTTT tags

Bug: 384793956
Flag: EXEMPT removing com.android.graphics.hwui.flags.high_contrast_text_luminance
Test: atest frameworks/base/core/tests/coretests/src/android/text/LayoutTest.java
Test: atest cts/tests/tests/uirendering/src/android/uirendering/cts/testclasses/TextViewHighContrastTextTests.kt
Change-Id: I86255f2a1ea5bb5a95ad2d1714d239141ab5bd74

3 files changed, 9 insertions, 29 deletions

diff --git a/core/java/android/text/Layout.java b/core/java/android/text/Layout.java
index d53b98c65f9a..3c53506990d1 100644
--- a/core/java/android/text/Layout.java
+++ b/core/java/android/text/Layout.java
@@ -16,7 +16,6 @@
 
 package android.text;
 
-import static com.android.graphics.hwui.flags.Flags.highContrastTextLuminance;
 import static com.android.text.flags.Flags.FLAG_FIX_LINE_HEIGHT_FOR_LOCALE;
 import static com.android.text.flags.Flags.FLAG_LETTER_SPACING_JUSTIFICATION;
 import static com.android.text.flags.Flags.FLAG_USE_BOUNDS_FOR_WIDTH;
@@ -670,15 +669,11 @@ public abstract class Layout {
         // High-contrast text mode
         // Determine if the text is black-on-white or white-on-black, so we know what blendmode will
         // give the highest contrast and most realistic text color.
-        // This equation should match the one in libs/hwui/hwui/DrawTextFunctor.h
-        if (highContrastTextLuminance()) {
-            var lab = new double[3];
-            ColorUtils.colorToLAB(color, lab);
-            return lab[0] < 50.0;
-        } else {
-            int channelSum = Color.red(color) + Color.green(color) + Color.blue(color);
-            return channelSum < (128 * 3);
-        }
+        // LINT.IfChange(hct_darken)
+        var lab = new double[3];
+        ColorUtils.colorToLAB(color, lab);
+        return lab[0] < 50.0;
+        // LINT.ThenChange(/libs/hwui/hwui/DrawTextFunctor.h:hct_darken)
     }
 
     private boolean isJustificationRequired(int lineNum) {
diff --git a/libs/hwui/aconfig/hwui_flags.aconfig b/libs/hwui/aconfig/hwui_flags.aconfig
index 76ad2acccf89..5e71d3360f39 100644
--- a/libs/hwui/aconfig/hwui_flags.aconfig
+++ b/libs/hwui/aconfig/hwui_flags.aconfig
@@ -34,13 +34,6 @@ flag {
 }
 
 flag {
-  name: "high_contrast_text_luminance"
-  namespace: "accessibility"
-  description: "Use luminance to determine how to make text more high contrast, instead of RGB heuristic"
-  bug: "186567103"
-}
-
-flag {
   name: "high_contrast_text_small_text_rect"
   namespace: "accessibility"
   description: "Draw a solid rectangle background behind text instead of a stroke outline"
diff --git a/libs/hwui/hwui/DrawTextFunctor.h b/libs/hwui/hwui/DrawTextFunctor.h
index e13e136550ca..e05c3d695463 100644
--- a/libs/hwui/hwui/DrawTextFunctor.h
+++ b/libs/hwui/hwui/DrawTextFunctor.h
@@ -34,9 +34,6 @@
 namespace flags = com::android::graphics::hwui::flags;
 #else
 namespace flags {
-constexpr bool high_contrast_text_luminance() {
-    return false;
-}
 constexpr bool high_contrast_text_small_text_rect() {
     return false;
 }
@@ -114,15 +111,10 @@ public:
         if (CC_UNLIKELY(canvas->isHighContrastText() && paint.getAlpha() != 0)) {
             // high contrast draw path
             int color = paint.getColor();
-            bool darken;
-            // This equation should match the one in core/java/android/text/Layout.java
-            if (flags::high_contrast_text_luminance()) {
-                uirenderer::Lab lab = uirenderer::sRGBToLab(color);
-                darken = lab.L <= 50;
-            } else {
-                int channelSum = SkColorGetR(color) + SkColorGetG(color) + SkColorGetB(color);
-                darken = channelSum < (128 * 3);
-            }
+            // LINT.IfChange(hct_darken)
+            uirenderer::Lab lab = uirenderer::sRGBToLab(color);
+            bool darken = lab.L <= 50;
+            // LINT.ThenChange(/core/java/android/text/Layout.java:hct_darken)
 
             // outline
             gDrawTextBlobMode = DrawTextBlobMode::HctOutline;