Android TextInput: Improve application of styles for value prop

Prior to this change, when you passed text to `TextInput` via the `value` or `defaultValue` props, React Native didn't apply any of the styles in `buildSpannedFromShadowNode` to the text. This is because `spannedFromShadowNode` appends `value` after calling `buildSpannedFromShadowNode`. Many styles worked because their logic is included in both `buildSpannedFromShadowNode` and `ReactTextInputManager`. However, some only appear in `buildSpannedFromShadowNode` such as `textDecorationLine` (it would be good to understand why we need to duplicate styling logic in `buildSpannedFromShadowNode` & `ReactTextInputManager` and to know whether `ReactTextInputManager` should be handling `textDecorationLine`).

Also, this commit improves consistency between iOS and Android if you specify both `value` and children on a `TextInput`. Prior to this, iOS concatenated the strings such that the `value` prop came before the children whereas Android put the children before the `value` prop. Now Android matches iOS's behavior and puts the `value` prop before the children.

These appear to be regressions. The `value` prop used to be appended before calling `buildSpannedFromShadowNode` (this behavior appears to have been changed by accident in 80027ce#diff-4f5947f2fe0381c4a6373a30e596b8c3).

The fix is done by pulling the logic that applies styling out of `buildSpannedFromShadowNode` and into a method `applyStyles`. The `value` prop is styled via `applyStyles` and then the children are styled and appended to it.

Test Plan:
----------

Used a variety of props to style some `TextInputs` (e.g. `textDecorationLine`, `fontSize`, `letterSpacing`). Verified that the `TextInputs` looked the same regardless of whether the text was provided via the `value` prop, children, or both.

Changelog:
----------

[Android] [Fixed] - TextInput: Improve application of styles for `value` prop

Adam Comella
Microsoft Corp.

ReactAndroid/src/main/java/com/facebook/react/views/text/ReactBaseTextShadowNode.java

@@ -113,76 +113,85 @@ private static void buildSpannedFromShadowNode(
     }
     int end = sb.length();
     if (end >= start) {
-      if (textShadowNode.mIsColorSet) {
-        ops.add(new SetSpanOperation(start, end, new ForegroundColorSpan(textShadowNode.mColor)));
-      }
-      if (textShadowNode.mIsBackgroundColorSet) {
-        ops.add(
-            new SetSpanOperation(
-                start, end, new BackgroundColorSpan(textShadowNode.mBackgroundColor)));
-      }
-      if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
-        if (!Float.isNaN(textShadowNode.mLetterSpacing)) {
-          ops.add(new SetSpanOperation(
-            start,
-            end,
-            new CustomLetterSpacingSpan(textShadowNode.mLetterSpacing)));
-        }
-      }
-      if (textShadowNode.mFontSize != UNSET) {
-        ops.add(new SetSpanOperation(start, end, new AbsoluteSizeSpan(textShadowNode.mFontSize)));
-      }
-      if (textShadowNode.mFontStyle != UNSET
-          || textShadowNode.mFontWeight != UNSET
-          || textShadowNode.mFontFamily != null) {
-        ops.add(
-            new SetSpanOperation(
-                start,
-                end,
-                new CustomStyleSpan(
-                    textShadowNode.mFontStyle,
-                    textShadowNode.mFontWeight,
-                    textShadowNode.mFontFamily,
-                    textShadowNode.getThemedContext().getAssets())));
-      }
-      if (textShadowNode.mIsUnderlineTextDecorationSet) {
-        ops.add(new SetSpanOperation(start, end, new UnderlineSpan()));
-      }
-      if (textShadowNode.mIsLineThroughTextDecorationSet) {
-        ops.add(new SetSpanOperation(start, end, new StrikethroughSpan()));
-      }
-      if (
-        (
-          textShadowNode.mTextShadowOffsetDx != 0 ||
-          textShadowNode.mTextShadowOffsetDy != 0 ||
-          textShadowNode.mTextShadowRadius != 0
-        ) &&
-        Color.alpha(textShadowNode.mTextShadowColor) != 0
-      ) {
-        ops.add(
-            new SetSpanOperation(
-                start,
-                end,
-                new ShadowStyleSpan(
-                    textShadowNode.mTextShadowOffsetDx,
-                    textShadowNode.mTextShadowOffsetDy,
-                    textShadowNode.mTextShadowRadius,
-                    textShadowNode.mTextShadowColor)));
-      }
-      if (!Float.isNaN(textShadowNode.getEffectiveLineHeight())) {
-        ops.add(
-            new SetSpanOperation(
-                start, end, new CustomLineHeightSpan(textShadowNode.getEffectiveLineHeight())));
-      }
-      if (textShadowNode.mTextTransform != TextTransform.UNSET) {
-        ops.add(
+      applyStyles(textShadowNode, sb, ops, start, end);
+    }
+  }
+
+  private static void applyStyles(
+      ReactBaseTextShadowNode textShadowNode,
+      SpannableStringBuilder sb,
+      List<SetSpanOperation> ops,
+      int start,
+      int end) {
+    if (textShadowNode.mIsColorSet) {
+      ops.add(new SetSpanOperation(start, end, new ForegroundColorSpan(textShadowNode.mColor)));
+    }
+    if (textShadowNode.mIsBackgroundColorSet) {
+      ops.add(
           new SetSpanOperation(
-            start,
-            end,
-            new CustomTextTransformSpan(textShadowNode.mTextTransform)));
+              start, end, new BackgroundColorSpan(textShadowNode.mBackgroundColor)));
+    }
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+      if (!Float.isNaN(textShadowNode.mLetterSpacing)) {
+        ops.add(new SetSpanOperation(
+          start,
+          end,
+          new CustomLetterSpacingSpan(textShadowNode.mLetterSpacing)));
       }
-      ops.add(new SetSpanOperation(start, end, new ReactTagSpan(textShadowNode.getReactTag())));
     }
+    if (textShadowNode.mFontSize != UNSET) {
+      ops.add(new SetSpanOperation(start, end, new AbsoluteSizeSpan(textShadowNode.mFontSize)));
+    }
+    if (textShadowNode.mFontStyle != UNSET
+        || textShadowNode.mFontWeight != UNSET
+        || textShadowNode.mFontFamily != null) {
+      ops.add(
+          new SetSpanOperation(
+              start,
+              end,
+              new CustomStyleSpan(
+                  textShadowNode.mFontStyle,
+                  textShadowNode.mFontWeight,
+                  textShadowNode.mFontFamily,
+                  textShadowNode.getThemedContext().getAssets())));
+    }
+    if (textShadowNode.mIsUnderlineTextDecorationSet) {
+      ops.add(new SetSpanOperation(start, end, new UnderlineSpan()));
+    }
+    if (textShadowNode.mIsLineThroughTextDecorationSet) {
+      ops.add(new SetSpanOperation(start, end, new StrikethroughSpan()));
+    }
+    if (
+      (
+        textShadowNode.mTextShadowOffsetDx != 0 ||
+        textShadowNode.mTextShadowOffsetDy != 0 ||
+        textShadowNode.mTextShadowRadius != 0
+      ) &&
+      Color.alpha(textShadowNode.mTextShadowColor) != 0
+    ) {
+      ops.add(
+          new SetSpanOperation(
+              start,
+              end,
+              new ShadowStyleSpan(
+                  textShadowNode.mTextShadowOffsetDx,
+                  textShadowNode.mTextShadowOffsetDy,
+                  textShadowNode.mTextShadowRadius,
+                  textShadowNode.mTextShadowColor)));
+    }
+    if (!Float.isNaN(textShadowNode.getEffectiveLineHeight())) {
+      ops.add(
+          new SetSpanOperation(
+              start, end, new CustomLineHeightSpan(textShadowNode.getEffectiveLineHeight())));
+    }
+    if (textShadowNode.mTextTransform != TextTransform.UNSET) {
+      ops.add(
+        new SetSpanOperation(
+          start,
+          end,
+          new CustomTextTransformSpan(textShadowNode.mTextTransform)));
+    }
+    ops.add(new SetSpanOperation(start, end, new ReactTagSpan(textShadowNode.getReactTag())));
   }
 
   protected int getDefaultFontSize() {
@@ -201,12 +210,15 @@ protected static Spannable spannedFromShadowNode(
     // a new spannable will be wiped out
     List<SetSpanOperation> ops = new ArrayList<>();
 
-    buildSpannedFromShadowNode(textShadowNode, sb, ops);
-
     if (text != null) {
+      // Handle text that is provided via a prop (e.g. the `value` and `defaultValue` props on
+      // TextInput).
       sb.append(text);
+      applyStyles(textShadowNode, sb, ops, 0, sb.length());
     }
 
+    buildSpannedFromShadowNode(textShadowNode, sb, ops);
+
     if (textShadowNode.mFontSize == UNSET) {
       int defaultFontSize = textShadowNode.getDefaultFontSize();