Instrumented libraries: Remove Precise support

third_party/instrumented_libraries/patches/libxcb1.precise.diff

-diff -rupN ./src/xcb_conn.c ../libxcb-1.8.1-patched/src/xcb_conn.c
---- ./src/xcb_conn.c    2012-01-11 21:05:41.000000000 +0400
-+++ ../libxcb-1.8.1-patched/src/xcb_conn.c      2014-12-10 23:37:44.432834622 +0300
-@@ -418,10 +418,20 @@ int _xcb_conn_wait(xcb_connection_t *c,
- 
-     if(ret)
-     {
-+        /* The code allows two threads to call select()/poll() at the same time.
-+         * First thread just wants to read, a second thread wants to write, too.
-+         * We have to make sure that we don't steal the reading thread's reply
-+         * and let it get stuck in select()/poll().
-+         * So a thread may read if either:
-+         * - There is no other thread that wants to read (the above situation
-+         *   did not occur).
-+         * - It is the reading thread (above situation occurred).
-+         */
-+        int may_read = c->in.reading == 1 || !count;
- #if USE_POLL
--        if((fd.revents & POLLIN) == POLLIN)
-+        if(may_read && (fd.revents & POLLIN) == POLLIN)
- #else
--        if(FD_ISSET(c->fd, &rfds))
-+        if(may_read && FD_ISSET(c->fd, &rfds))
- #endif
-             ret = ret && _xcb_in_read(c);
-