Moved svn 1.6 version check into VCSUtils::isSVNVersion16OrNewer()

        Reviewed by Eric Seidel.

        * Scripts/VCSUtils.pm:
        (@EXPORT): Added &isSVNVersion16OrNewer.
        (svnVersion): Added.  Internal method that gets the SVN version
        and caches it.
        (isSVNVersion16OrNewer): Added.  Method that does the SVN 1.6
        version check.
        * Scripts/prepare-ChangeLog: Switched to use new
        isSVNVersion16OrNewer() method.
        * Scripts/resolve-ChangeLogs: Ditto.
        * Scripts/svn-create-patch: Ditto.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@47970 268f45cc-cd09-0410-ab3c-d52691b4dbfc
diff --git a/WebKitTools/Scripts/prepare-ChangeLog b/WebKitTools/Scripts/prepare-ChangeLog
index 19842bc..1f79081 100755
--- a/WebKitTools/Scripts/prepare-ChangeLog
+++ b/WebKitTools/Scripts/prepare-ChangeLog
@@ -151,8 +151,6 @@
 my $SVN = "svn";
 my $GIT = "git";
 
-my $svnVersion = `svn --version --quiet` if $isSVN;
-
 # Find the list of modified files
 my @changed_files;
 my $changed_files_string;
@@ -1438,7 +1436,7 @@
 
         if ($isSVN) {
             my $matches;
-            if (eval "v$svnVersion" ge v1.6) {
+            if (isSVNVersion16OrNewer()) {
                 $matches = /^([ ACDMR])([ CM]).{5} (.+?)[\r\n]*$/;
                 $status = $1;
                 $propertyStatus = $2;