Preserve columnized arrays, even if they have a single column

This change preservers existing whitespace for arrays where each element
is on a separate line, e.g.:

new int[]{
  1,
  2,
  3,
};

Previously this was only done if each row had two or more elements:

new int[]{
  1, 2,
  3, 4,
  5, 6,
};

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=155128355

Author: cushon

core/src/main/java/com/google/googlejavaformat/java/JavaInputAstVisitor.java

@@ -471,7 +471,7 @@ public boolean visitArrayInitializer(List<? extends ExpressionTree> expressions)
         if (!first) {
           builder.forcedBreak();
         }
-        builder.open(row.iterator().next().getKind() == NEW_ARRAY ? ZERO : plusFour);
+        builder.open(row.iterator().next().getKind() == NEW_ARRAY || cols == 1 ? ZERO : plusFour);
         boolean firstInRow = true;
         for (ExpressionTree item : row) {
           if (!firstInRow) {
@@ -2889,7 +2889,10 @@ private int argumentsAreTabular(List<? extends ExpressionTree> arguments) {
       while (it.hasNext() && actualColumn(it.peek()) > start0) {
         row.add(it.next());
       }
-      if (!it.hasNext() || row.size() == 1) {
+      if (!it.hasNext()) {
+        return -1;
+      }
+      if (rowLength(row) <= 1) {
         return -1;
       }
       rows.add(row);
@@ -2934,6 +2937,23 @@ private int argumentsAreTabular(List<? extends ExpressionTree> arguments) {
     return size0;
   }
 
+  static int rowLength(List<? extends ExpressionTree> row) {
+    int size = 0;
+    for (ExpressionTree tree : row) {
+      if (tree.getKind() != NEW_ARRAY) {
+        size++;
+        continue;
+      }
+      NewArrayTree array = (NewArrayTree) tree;
+      if (array.getInitializers() == null) {
+        size++;
+        continue;
+      }
+      size += rowLength(array.getInitializers());
+    }
+    return size;
+  }
+
   private Integer actualColumn(ExpressionTree expression) {
     Map<Integer, Integer> positionToColumnMap = builder.getInput().getPositionToColumnMap();
     return positionToColumnMap.get(builder.actualStartColumn(getStartPosition(expression)));

core/src/test/resources/com/google/googlejavaformat/java/testdata/B37895033.input

@@ -0,0 +1,20 @@
+class B37895033 {
+  String[][] xs =
+      new String[][] {
+        {"B3", "C3", "D3"},
+        {"B4", "C4", "D4"},
+        {"B5", "C5", "D5"}
+      };
+  String[] ys =
+      new String[] {
+        "B3",
+        "B4",
+        "B5",
+      };
+  String[][] zs =
+      new String[][] {
+        {"B3"},
+        {"B4"},
+        {"B5"},
+      };
+}

core/src/test/resources/com/google/googlejavaformat/java/testdata/B37895033.output

@@ -0,0 +1,16 @@
+class B37895033 {
+  String[][] xs =
+      new String[][] {
+        {"B3", "C3", "D3"},
+        {"B4", "C4", "D4"},
+        {"B5", "C5", "D5"}
+      };
+  String[] ys =
+      new String[] {
+        "B3", "B4", "B5",
+      };
+  String[][] zs =
+      new String[][] {
+        {"B3"}, {"B4"}, {"B5"},
+      };
+}