Update ICU4J NumberRegression.

In a recent change to android.icu.DecimalFormat we increased the maximum
integer digits to 2 billion to be consistent with the ICU4C
implementation and support java.text.DecimalFormat.

This change updates the serialization regression test to coincide with
that chage.

Bug: 28397841
Bug: 27855939

(cherry picked from commit b6fbe956afc8bf4c8e47fc2e6ce6680f6043ba7b)

Change-Id: I154d23612f4dadf07ea918c739aa54597c22cc76
diff --git a/android_icu4j/src/main/tests/android/icu/dev/test/format/NumberRegression.java b/android_icu4j/src/main/tests/android/icu/dev/test/format/NumberRegression.java
index e7684cd..2c4915b 100644
--- a/android_icu4j/src/main/tests/android/icu/dev/test/format/NumberRegression.java
+++ b/android_icu4j/src/main/tests/android/icu/dev/test/format/NumberRegression.java
@@ -1448,13 +1448,17 @@
         for (int i = 0; i < offsets.length; ++i) {
             bytes[offsets[i]] = 4;
         }
+        // Android patch (http://b/27855939) start.
+        // Allow 2 billion integer digits.
+        bytes[offsets[1]-2] = 127;
 
         {
             ObjectInputStream ois = new ObjectInputStream(new ByteArrayInputStream(bytes));
             NumberFormat format = (NumberFormat) ois.readObject();
             //For compatibility with previous version
-            if ((format.getMaximumIntegerDigits() != 309) 
+            if ((format.getMaximumIntegerDigits() != 2000000000)
                 || format.getMaximumFractionDigits() != 340) {
+                // Android patch (http://b/27855939) end.
                 errln("FAIL: Deserialized bogus NumberFormat with values out of range," +
                       " intMin: " + format.getMinimumIntegerDigits() +
                       " intMax: " + format.getMaximumIntegerDigits() +
diff --git a/icu4j/main/tests/core/src/com/ibm/icu/dev/test/format/NumberRegression.java b/icu4j/main/tests/core/src/com/ibm/icu/dev/test/format/NumberRegression.java
index dd6d542..0851760 100644
--- a/icu4j/main/tests/core/src/com/ibm/icu/dev/test/format/NumberRegression.java
+++ b/icu4j/main/tests/core/src/com/ibm/icu/dev/test/format/NumberRegression.java
@@ -1444,13 +1444,17 @@
         for (int i = 0; i < offsets.length; ++i) {
             bytes[offsets[i]] = 4;
         }
+        // Android patch (http://b/27855939) start.
+        // Allow 2 billion integer digits.
+        bytes[offsets[1]-2] = 127;
 
         {
             ObjectInputStream ois = new ObjectInputStream(new ByteArrayInputStream(bytes));
             NumberFormat format = (NumberFormat) ois.readObject();
             //For compatibility with previous version
-            if ((format.getMaximumIntegerDigits() != 309) 
+            if ((format.getMaximumIntegerDigits() != 2000000000)
                 || format.getMaximumFractionDigits() != 340) {
+                // Android patch (http://b/27855939) end.
                 errln("FAIL: Deserialized bogus NumberFormat with values out of range," +
                       " intMin: " + format.getMinimumIntegerDigits() +
                       " intMax: " + format.getMaximumIntegerDigits() +