[LayoutTest] Fix xmlhttprequest-responseXML-nopartial flakiness.

LayoutTests/http/tests/xmlhttprequest/resources/small-chunks.cgi

Index: LayoutTests/http/tests/xmlhttprequest/resources/small-chunks.cgi
diff --git a/LayoutTests/http/tests/xmlhttprequest/resources/small-chunks.cgi b/LayoutTests/http/tests/xmlhttprequest/resources/small-chunks.cgi
index 0225a4ce102b245cc7ecdc0c266d94948b6344b2..3d37b574f01ddab908f0810383f2e20c6696836c 100755
--- a/LayoutTests/http/tests/xmlhttprequest/resources/small-chunks.cgi
+++ b/LayoutTests/http/tests/xmlhttprequest/resources/small-chunks.cgi
@@ -1,6 +1,7 @@
 #!/usr/bin/perl
 
 use IO::Socket;
+use Time::HiRes qw(sleep);
 
 $| = 1;
 
@@ -10,5 +11,5 @@ print "Content-Type: text/html; charset=ISO-8859-1\n\n";
 
 for (my $i = 0; $i < 5; $i++) {
     print "This is chunk number $i";
-    sleep 1;
+    sleep 0.1;
 }