Text: using utility function instead of own (bugged) implementation.

Also removed the test, as there is now nothing to test.

src/Text/AbstractFont.cpp

@@ -106,16 +106,7 @@ void AbstractFont::close() {
 void AbstractFont::createGlyphCache(GlyphCache* const cache, const std::string& characters) {
     CORRADE_ASSERT(isOpened(), "Text::AbstractFont::createGlyphCache(): no font opened", );
 
-    /* Get glyph codes from characters */
-    std::u32string unicodeCharacters;
-    unicodeCharacters.reserve(characters.size()+1);
-    for(std::size_t i = 0; i != characters.size(); ) {
-        char32_t unicode;
-        std::tie(unicode, i) = Utility::Unicode::nextChar(characters, i);
-        unicodeCharacters.push_back(unicode);
-    }
-
-    doCreateGlyphCache(cache, unicodeCharacters);
+    doCreateGlyphCache(cache, Utility::Unicode::utf32(characters));
 }
 
 AbstractLayouter* AbstractFont::layout(const GlyphCache* const cache, const Float size, const std::string& text) {

src/Text/Test/AbstractFontTest.cpp

@@ -38,15 +38,11 @@ class AbstractFontTest: public TestSuite::Tester {
 
         void openSingleData();
         void openFile();
-
-        void createGlyphCache();
 };
 
 AbstractFontTest::AbstractFontTest() {
     addTests({&AbstractFontTest::openSingleData,
-              &AbstractFontTest::openFile,
-
-              &AbstractFontTest::createGlyphCache});
+              &AbstractFontTest::openFile});
 }
 
 namespace {
@@ -89,30 +85,6 @@ void AbstractFontTest::openFile() {
     CORRADE_VERIFY(font.isOpened());
 }
 
-void AbstractFontTest::createGlyphCache() {
-    class CachingFont: public Text::AbstractFont {
-        public:
-            std::u32string cacheCharacters;
-
-        private:
-            Features doFeatures() const override { return {}; }
-            bool doIsOpened() const override { return true; }
-            void doClose() override {}
-
-            void doCreateGlyphCache(GlyphCache*, const std::u32string& characters) override {
-                cacheCharacters = characters;
-            }
-
-            AbstractLayouter* doLayout(const GlyphCache*, Float, const std::string&) override {
-                return nullptr;
-            }
-    };
-
-    CachingFont font;
-    font.createGlyphCache(nullptr, "žluťoučký kůň");
-    CORRADE_COMPARE(font.cacheCharacters, U"\u017Elu\u0165ou\u010Dk\u00FD k\u016F\u0148");
-}
-
 }}}
 
 CORRADE_TEST_MAIN(Magnum::Text::Test::AbstractFontTest)