Fix wrong offset of BiDi text by TextShaper

This CL includes:
- Fix relative offset of BidiRun by reviving width calculation in TextLine.
- Fix bidi level buffer offset. It shuold be relative to the substring, but
  the absolute offset was passed.
- Removed paint argument from PositionedGlyph which is not used.

Bug: 171275519
Test: atest android.graphics.text.cts.TextRunShaperTest
Test: atest android.text.cts.TextShaperTest

Change-Id: I36949089d744bdfae61995210b2051866a7510ac

core/java/android/text/TextLine.java

@@ -931,7 +931,8 @@ public class TextLine {
         float totalWidth = 0;
 
         final int numDecorations = decorations == null ? 0 : decorations.size();
-        if (needWidth || (c != null && (wp.bgColor != 0 || numDecorations != 0 || runIsRtl))) {
+        if (needWidth || ((c != null || consumer != null) && (wp.bgColor != 0
+                || numDecorations != 0 || runIsRtl))) {
             totalWidth = getRunAdvance(wp, start, end, contextStart, contextEnd, runIsRtl, offset);
         }
 

core/java/android/text/TextShaper.java

@@ -198,6 +198,10 @@ public class TextShaper {
     /**
      * Shape multi-styled text.
      *
+     * In the LTR context, the shape result will go from left to right, thus you may want to draw
+     * glyphs from left most position of the canvas. In the RTL context, the shape result will go
+     * from right to left, thus you may want to draw glyphs from right most position of the canvas.
+     *
      * @param text a styled text.
      * @param start a start index of shaping target in the text.
      * @param count a length of shaping target in the text.
@@ -215,7 +219,7 @@ public class TextShaper {
         try {
             tl.set(paint, text, start, start + count,
                     mp.getParagraphDir(),
-                    mp.getDirections(start, start + count),
+                    mp.getDirections(0, count),
                     false /* tabstop is not supported */,
                     null,
                     -1, -1 // ellipsis is not supported.

graphics/java/android/graphics/text/PositionedGlyphs.java

@@ -170,9 +170,8 @@ public final class PositionedGlyphs {
      * @hide
      *
      * @param layoutPtr the address of native layout object.
-     * @param paint a paint object
      */
-    public PositionedGlyphs(long layoutPtr, @NonNull Paint paint, float xOffset, float yOffset) {
+    public PositionedGlyphs(long layoutPtr, float xOffset, float yOffset) {
         mLayoutPtr = layoutPtr;
         int glyphCount = nGetGlyphCount(layoutPtr);
         mFonts = new ArrayList<>(glyphCount);

graphics/java/android/graphics/text/TextRunShaper.java

@@ -72,7 +72,7 @@ public class TextRunShaper {
         return new PositionedGlyphs(
                 nativeShapeTextRun(text, start, count, contextStart, contextCount, isRtl,
                         paint.getNativeInstance()),
-                paint, xOffset, yOffset);
+                xOffset, yOffset);
     }
 
     /**
@@ -104,7 +104,7 @@ public class TextRunShaper {
                     nativeShapeTextRun(
                             (String) text, start, count, contextStart, contextCount, isRtl,
                             paint.getNativeInstance()),
-                    paint, xOffset, yOffset);
+                    xOffset, yOffset);
         } else {
             char[] buf = new char[contextCount];
             TextUtils.getChars(text, contextStart, contextStart + contextCount, buf, 0);
@@ -112,7 +112,7 @@ public class TextRunShaper {
                     nativeShapeTextRun(
                             buf, start - contextStart, count,
                             0, contextCount, isRtl, paint.getNativeInstance()),
-                    paint, xOffset, yOffset);
+                    xOffset, yOffset);
         }
     }