Revert "Enable PrecomputedText for BiDi text"

This reverts commit 6224e238d6f0c48b419b99d6889997d83350f4e6.

Reason for revert: b/119659731

Change-Id: I33ea82d69d09f113d594446f8979f0df21200662
diff --git a/core/java/android/text/TextLine.java b/core/java/android/text/TextLine.java
index 6eb433a..7b638b4 100644
--- a/core/java/android/text/TextLine.java
+++ b/core/java/android/text/TextLine.java
@@ -201,7 +201,7 @@
             }
         }
 
-        mCharsValid = hasReplacement;
+        mCharsValid = hasReplacement || hasTabs || directions != Layout.DIRS_ALL_LEFT_TO_RIGHT;
 
         if (mCharsValid) {
             if (mChars == null || mChars.length < mLen) {
@@ -815,6 +815,7 @@
         } else {
             final int delta = mStart;
             if (mComputed == null) {
+                // TODO: Enable measured getRunAdvance for ReplacementSpan and RTL text.
                 return wp.getRunAdvance(mText, delta + start, delta + end,
                         delta + contextStart, delta + contextEnd, runIsRtl, delta + offset);
             } else {