diff --color-moved: clear all flags on blocks that are too short

If a block of potentially moved lines is not long enough then the
DIFF_SYMBOL_MOVED_LINE flag is cleared on the matching lines so they
are not marked as moved. To avoid problems when we start rewinding
after an unsuccessful match in a couple of commits time make sure all
the move related flags are cleared, not just DIFF_SYMBOL_MOVED_LINE.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/diff.c b/diff.c
index 52c7915..bd8e4ec 100644
--- a/diff.c
+++ b/diff.c
@@ -1114,6 +1114,8 @@ static int shrink_potential_moved_blocks(struct moved_block *pmb,
  * NEEDSWORK: This uses the same heuristic as blame_entry_score() in blame.c.
  * Think of a way to unify them.
  */
+#define DIFF_SYMBOL_MOVED_LINE_ZEBRA_MASK \
+  (DIFF_SYMBOL_MOVED_LINE | DIFF_SYMBOL_MOVED_LINE_ALT)
 static int adjust_last_block(struct diff_options *o, int n, int block_length)
 {
 	int i, alnum_count = 0;
@@ -1130,7 +1132,7 @@ static int adjust_last_block(struct diff_options *o, int n, int block_length)
 		}
 	}
 	for (i = 1; i < block_length + 1; i++)
-		o->emitted_symbols->buf[n - i].flags &= ~DIFF_SYMBOL_MOVED_LINE;
+		o->emitted_symbols->buf[n - i].flags &= ~DIFF_SYMBOL_MOVED_LINE_ZEBRA_MASK;
 	return 0;
 }
 
@@ -1237,8 +1239,6 @@ static void mark_color_as_moved(struct diff_options *o,
 	free(pmb);
 }
 
-#define DIFF_SYMBOL_MOVED_LINE_ZEBRA_MASK \
-  (DIFF_SYMBOL_MOVED_LINE | DIFF_SYMBOL_MOVED_LINE_ALT)
 static void dim_moved_lines(struct diff_options *o)
 {
 	int n;