Format a line if a range in its leading whitespace was selected.

With [] marking the selected range, clang-format invoked on

    [  ]   int a;

Would so far not reformat anything. With this patch, it formats a
line if its leading whitespace is touched.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176435 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Format/UnwrappedLineParser.h b/lib/Format/UnwrappedLineParser.h
index 5db5e7b..f4fecc5 100644
--- a/lib/Format/UnwrappedLineParser.h
+++ b/lib/Format/UnwrappedLineParser.h
@@ -33,8 +33,8 @@
 struct FormatToken {
   FormatToken()
       : NewlinesBefore(0), HasUnescapedNewline(false), WhiteSpaceLength(0),
-        TokenLength(0), IsFirst(false), MustBreakBefore(false) {
-  }
+        LastNewlineOffset(0), TokenLength(0), IsFirst(false),
+        MustBreakBefore(false) {}
 
   /// \brief The \c Token.
   Token Tok;
@@ -59,6 +59,10 @@
   /// the \c Token.
   unsigned WhiteSpaceLength;
 
+  /// \brief The offset just past the last '\n' in this token's leading
+  /// whitespace (relative to \c WhiteSpaceStart). 0 if there is no '\n'.
+  unsigned LastNewlineOffset;
+
   /// \brief The length of the non-whitespace parts of the token. This is
   /// necessary because we need to handle escaped newlines that are stored
   /// with the token.