Merge "docs(non linear font scaling): deprecate TypedValue.scaledDensity and add warning on Configuration.fontScale"

core/api/current.txt

@@ -48672,7 +48672,7 @@ package android.util {
     field public float density;
     field public int densityDpi;
     field public int heightPixels;
-    field public float scaledDensity;
+    field @Deprecated public float scaledDensity;
     field public int widthPixels;
     field public float xdpi;
     field public float ydpi;

core/java/android/content/res/Configuration.java

@@ -98,6 +98,14 @@ public final class Configuration implements Parcelable, Comparable<Configuration
     /**
      * Current user preference for the scaling factor for fonts, relative
      * to the base density scaling.
+     *
+     * <p>Note: Please do not use this to hardcode font size equations. The equation for font
+     * scaling is now non-linear; this coefficient is no longer used as a direct multiplier to
+     * determine font size. It exists for informational purposes only.
+     *
+     * <p>Please use {@link android.util.TypedValue#applyDimension(int, float, DisplayMetrics)} or
+     * {@link android.util.TypedValue#deriveDimension(int, float, DisplayMetrics)} to convert
+     * between scaled font size dimensions and pixels.
      */
     public float fontScale;
 

core/java/android/util/DisplayMetrics.java

@@ -283,7 +283,13 @@ public class DisplayMetrics {
      * A scaling factor for fonts displayed on the display.  This is the same
      * as {@link #density}, except that it may be adjusted in smaller
      * increments at runtime based on a user preference for the font size.
+     *
+     * @deprecated this scalar factor is no longer accurate due to adaptive non-linear font scaling.
+     *  Please use {@link TypedValue#applyDimension(int, float, DisplayMetrics)} or
+     *  {@link TypedValue#deriveDimension(int, float, DisplayMetrics)} to convert between SP font
+     *  sizes and pixels.
      */
+    @Deprecated
     public float scaledDensity;
 
     /**