Match window role in Rules in a case insensitive manner

Summary:
We used to have a toLower when reading the rule. This was removed with
4f7edb8d which turned it into a case sensitive matching to fix a
regression.

But this created another regression: existing rules written lower case
are no longer matched.

This change makes the role matching case insensitive again.

BUG: 367554

Reviewers: #kwin

Subscribers: kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D2574

autotests/integration/window_rules_test.cpp

@@ -154,7 +154,6 @@ void WindowRuleTest::testApplyInitialMaximizeVert()
     QVERIFY(surfaceChangedSpy.isValid());
     QVERIFY(surfaceChangedSpy.wait());
     QVERIFY(client->surface());
-    QEXPECT_FAIL("CamelCase", "BUG 367554", Continue);
     QCOMPARE(client->maximizeMode(), MaximizeVertical);
 
     // destroy window again

rules.cpp

@@ -141,7 +141,7 @@ void Rules::readFromCfg(const KConfigGroup& cfg)
         description = cfg.readEntry("description");
     READ_MATCH_STRING(wmclass, .toLower().toLatin1());
     wmclasscomplete = cfg.readEntry("wmclasscomplete" , false);
-    READ_MATCH_STRING(windowrole, .toLatin1());
+    READ_MATCH_STRING(windowrole, .toLower().toLatin1());
     READ_MATCH_STRING(title,);
     READ_MATCH_STRING(clientmachine, .toLower().toLatin1());
     types = NET::WindowTypeMask(cfg.readEntry<uint>("types", NET::AllTypesMask));
@@ -451,7 +451,7 @@ bool Rules::match(const Client* c) const
         return false;
     if (!matchWMClass(c->resourceClass(), c->resourceName()))
         return false;
-    if (!matchRole(c->windowRole()))
+    if (!matchRole(c->windowRole().toLower()))
         return false;
     if (!matchClientMachine(c->clientMachine()->hostName(), c->clientMachine()->isLocal()))
         return false;