LibCore: Put all classes in the Core namespace and remove the leading C

I've been wanting to do this for a long time. It's time we start being
consistent about how this stuff works.

The new convention is:

- "LibFoo" is a userspace library that provides the "Foo" namespace.

That's it :^) This was pretty tedious to convert and I didn't even
start on LibGUI yet. But it's coming up next.

Libraries/LibHTML/CSS/StyleProperties.cpp

@@ -109,7 +109,7 @@ void StyleProperties::load_font() const
 
     auto look_for_file = [](const StringView& expected_name) -> String {
         // TODO: handle font sizes properly?
-        CDirIterator it { "/res/fonts/", CDirIterator::Flags::SkipDots };
+        Core::DirIterator it { "/res/fonts/", Core::DirIterator::Flags::SkipDots };
         while (it.has_next()) {
             String name = it.next_path();
             ASSERT(name.ends_with(".font"));

Libraries/LibHTML/CodeGenerators/Generate_CSS_PropertyID_cpp/Generate_CSS_PropertyID_cpp.cpp

@@ -51,8 +51,8 @@ int main(int argc, char** argv)
         fprintf(stderr, "usage: %s <path/to/CSS/Properties.json>\n", argv[0]);
         return 1;
     }
-    auto file = CFile::construct(argv[1]);
-    if (!file->open(CIODevice::ReadOnly))
+    auto file = Core::File::construct(argv[1]);
+    if (!file->open(Core::IODevice::ReadOnly))
         return 1;
 
     auto json = JsonValue::from_string(file->read_all());

Libraries/LibHTML/CodeGenerators/Generate_CSS_PropertyID_h/Generate_CSS_PropertyID_h.cpp

@@ -51,8 +51,8 @@ int main(int argc, char** argv)
         fprintf(stderr, "usage: %s <path/to/CSS/Properties.json>\n", argv[0]);
         return 1;
     }
-    auto file = CFile::construct(argv[1]);
-    if (!file->open(CIODevice::ReadOnly))
+    auto file = Core::File::construct(argv[1]);
+    if (!file->open(Core::IODevice::ReadOnly))
         return 1;
 
     auto json = JsonValue::from_string(file->read_all());

Libraries/LibHTML/DOM/Document.cpp

@@ -47,7 +47,7 @@ Document::Document()
     : ParentNode(*this, NodeType::DOCUMENT_NODE)
     , m_style_resolver(make<StyleResolver>(*this))
 {
-    m_style_update_timer = CTimer::construct();
+    m_style_update_timer = Core::Timer::construct();
     m_style_update_timer->set_single_shot(true);
     m_style_update_timer->set_interval(0);
     m_style_update_timer->on_timeout = [this] {

Libraries/LibHTML/DOM/Document.h

@@ -36,8 +36,11 @@
 #include <LibHTML/CSS/StyleSheet.h>
 #include <LibHTML/DOM/ParentNode.h>
 
+namespace Core {
+class Timer;
+}
+
 class Palette;
-class CTimer;
 class Frame;
 class HTMLBodyElement;
 class HTMLHtmlElement;
@@ -135,7 +138,7 @@ private:
     Optional<Color> m_active_link_color;
     Optional<Color> m_visited_link_color;
 
-    RefPtr<CTimer> m_style_update_timer;
+    RefPtr<Core::Timer> m_style_update_timer;
 
     String m_source;
 };

Libraries/LibHTML/DOM/HTMLBlinkElement.cpp

@@ -32,7 +32,7 @@
 
 HTMLBlinkElement::HTMLBlinkElement(Document& document, const String& tag_name)
     : HTMLElement(document, tag_name)
-    , m_timer(CTimer::construct())
+    , m_timer(Core::Timer::construct())
 {
     m_timer->set_interval(500);
     m_timer->on_timeout = [this] { blink(); };

Libraries/LibHTML/DOM/HTMLBlinkElement.h

@@ -28,7 +28,9 @@
 
 #include <LibHTML/DOM/HTMLElement.h>
 
-class CTimer;
+namespace Core {
+class Timer;
+}
 
 class HTMLBlinkElement : public HTMLElement {
 public:
@@ -38,5 +40,5 @@ public:
 private:
     void blink();
 
-    NonnullRefPtr<CTimer> m_timer;
+    NonnullRefPtr<Core::Timer> m_timer;
 };

Libraries/LibHTML/ResourceLoader.cpp

@@ -46,9 +46,9 @@ ResourceLoader::ResourceLoader()
 void ResourceLoader::load(const URL& url, Function<void(const ByteBuffer&)> callback)
 {
     if (url.protocol() == "file") {
-        auto f = CFile::construct();
+        auto f = Core::File::construct();
         f->set_filename(url.path());
-        if (!f->open(CIODevice::OpenMode::ReadOnly)) {
+        if (!f->open(Core::IODevice::OpenMode::ReadOnly)) {
             dbg() << "ResourceLoader::load: Error: " << f->error_string();
             callback({});
             return;

Libraries/LibHTML/ResourceLoader.h

@@ -34,7 +34,7 @@ namespace LibProtocol {
 class Client;
 }
 
-class ResourceLoader : public CObject {
+class ResourceLoader : public Core::Object {
     C_OBJECT(ResourceLoader)
 public:
     static ResourceLoader& the();