git: Fallback to git-clone for all snapshot failures.

Not just the minor failures.

modules/ksb/BuildException.pm

@@ -27,4 +27,10 @@ sub to_string
     return $exception->{exception_type} . " Error: " . $exception->{message};
 }
 
+sub message
+{
+    my $self = shift;
+    return $self->{message};
+}
+
 1;

modules/ksb/Updater/Git.pm

@@ -91,7 +91,10 @@ sub clone
 
     note ("\tCloning g[$module]");
 
-    if (!$self->installGitSnapshot()) {
+    my $result = eval { $self->installGitSnapshot() };
+
+    if (my $e = had_an_exception() || !$result) {
+        warning($e->message()) if $e;
         if (0 != log_command($module, 'git-clone', ['git', 'clone', @args])) {
             croak_runtime("Failed to make initial clone of $module");
         }

modules/ksb/Util.pm

@@ -22,8 +22,9 @@ use ksb::Version qw(scriptVersion);
 use ksb::BuildException;
 
 use Exporter qw(import); # Use Exporter's import method
-our @EXPORT = qw(list_has make_exception assert_isa assert_in any
-                 croak_runtime croak_internal download_file absPathToExecutable
+our @EXPORT = qw(list_has assert_isa assert_in any
+                 croak_runtime croak_internal had_an_exception make_exception
+                 download_file absPathToExecutable
                  fileDigestMD5 log_command disable_locale_message_translation
                  split_quoted_on_whitespace safe_unlink safe_system p_chdir
                  pretend_open safe_rmtree get_list_digest
@@ -88,6 +89,19 @@ sub make_exception
     return ksb::BuildException->new($exception_type, $message);
 }
 
+# Helper function to return $@ if $@ is a ksb::BuildException.
+#
+# This function assumes that an eval block had just been used in order to set or
+# clear $@ as appropriate.
+sub had_an_exception
+{
+    if ($@ && ref $@ && $@->isa('ksb::BuildException')) {
+        return $@;
+    }
+
+    return;
+}
+
 # Should be used for "runtime errors" (i.e. unrecoverable runtime problems that
 # don't indicate a bug in the program itself).
 sub croak_runtime