Fix clip_span() to use memmove() instead of memcpy().

This is actually a merge of upstream commit a44d715d2b19dc2f8f48b01144cc38e4e2c5015a

BUG=139587,132211
Review URL: https://chromiumcodereview.appspot.com/10833067

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@149148 0039d316-1c4b-4281-b951-d872f2087c98

third_party/mesa/MesaLib/src/mesa/swrast/s_span.c

@@ -762,7 +762,7 @@ clip_span( GLcontext *ctx, SWspan *span )
          span->intTex[1] += leftClip * span->intTexStep[1];
 
 #define SHIFT_ARRAY(ARRAY, SHIFT, LEN) \
-         memcpy(ARRAY, ARRAY + (SHIFT), (LEN) * sizeof(ARRAY[0]))
+         memmove(ARRAY, ARRAY + (SHIFT), (LEN) * sizeof(ARRAY[0]))
 
          for (i = 0; i < FRAG_ATTRIB_MAX; i++) {
             if (span->arrayAttribs & (1 << i)) {

third_party/mesa/README.chromium

@@ -98,3 +98,6 @@ Later modifications (see chromium.patch):
 
 - Merged fix for https://bugs.freedesktop.org/show_bug.cgi?id=51574
   (commit b1802a2115323233352da558430e109ff187b8af)
+
+- Merged the replacement of memcpy() with memmove() in SHIFT_ARRAY declared in
+  s_span.c (commit a44d715d2b19dc2f8f48b01144cc38e4e2c5015a)