Everywhere: Replace a bundle of dbg with dbgln.

These changes are arbitrarily divided into multiple commits to make it
easier to find potentially introduced bugs with git bisect.Everything:

The modifications in this commit were automatically made using the
following command:

    find . -name '*.cpp' -exec sed -i -E 's/dbg\(\) << ("[^"{]*");/dbgln\(\1\);/' {} \;

Libraries/LibWeb/CSS/Parser/CSSParser.cpp

@@ -41,9 +41,9 @@
         ASSERT_NOT_REACHED();                                             \
     }
 
-#define PARSE_ERROR()               \
-    do {                            \
-        dbg() << "CSS parse error"; \
+#define PARSE_ERROR()             \
+    do {                          \
+        dbgln("CSS parse error"); \
     } while (0)
 
 namespace Web {

Libraries/LibWeb/CodeGenerators/WrapperGenerator.cpp

@@ -356,14 +356,14 @@ int main(int argc, char** argv)
     }
 
 #if 0
-    dbg() << "Attributes:";
+    dbgln("Attributes:");
     for (auto& attribute : interface->attributes) {
         dbg() << "  " << (attribute.readonly ? "Readonly " : "")
               << attribute.type.name << (attribute.type.nullable ? "?" : "")
               << " " << attribute.name;
     }
 
-    dbg() << "Functions:";
+    dbgln("Functions:");
     for (auto& function : interface->functions) {
         dbg() << "  " << function.return_type.name << (function.return_type.nullable ? "?" : "")
               << " " << function.name;

Libraries/LibWeb/DOM/Node.cpp

@@ -190,7 +190,7 @@ RefPtr<Node> Node::insert_before(NonnullRefPtr<Node> node, RefPtr<Node> child, b
     if (!child)
         return append_child(move(node), notify);
     if (child->parent_node() != this) {
-        dbg() << "FIXME: Trying to insert_before() a bogus child";
+        dbgln("FIXME: Trying to insert_before() a bogus child");
         return nullptr;
     }
     if (&node->document() != &document())

Libraries/LibWeb/HTML/CanvasRenderingContext2D.cpp

@@ -207,7 +207,7 @@ void CanvasRenderingContext2D::fill(const String& fill_rule)
 RefPtr<ImageData> CanvasRenderingContext2D::create_image_data(int width, int height) const
 {
     if (!wrapper()) {
-        dbg() << "Hmm! Attempted to create ImageData for wrapper-less CRC2D.";
+        dbgln("Hmm! Attempted to create ImageData for wrapper-less CRC2D.");
         return nullptr;
     }
     return ImageData::create_with_size(wrapper()->global_object(), width, height);

Libraries/LibWeb/Loader/Resource.cpp

@@ -106,7 +106,7 @@ void Resource::did_load(Badge<ResourceLoader>, ReadonlyBytes data, const HashMap
         m_mime_type = url().data_mime_type();
     } else {
 #ifdef RESOURCE_DEBUG
-        dbg() << "No Content-Type header to go on! Guessing based on filename...";
+        dbgln("No Content-Type header to go on! Guessing based on filename...");
 #endif
         m_encoding = "utf-8"; // FIXME: This doesn't seem nice.
         m_mime_type = Core::guess_mime_type_based_on_filename(url().path());

Libraries/LibWeb/SVG/SVGPathElement.cpp

@@ -92,7 +92,7 @@ static void print_instruction(const PathInstruction& instruction)
             dbg() << "    (rx=" << data[i] << ", ry=" << data[i + 1] << ") x-axis-rotation=" << data[i + 2] << ", large-arc-flag=" << data[i + 3] << ", sweep-flag=" << data[i + 4] << ", (x=" << data[i + 5] << ", y=" << data[i + 6] << ")";
         break;
     case PathInstructionType::Invalid:
-        dbg() << "Invalid";
+        dbgln("Invalid");
         break;
     }
 }

Libraries/LibWeb/WebContentClient.cpp

@@ -70,7 +70,7 @@ void WebContentClient::handle(const Messages::WebContentClient::DidInvalidateCon
 void WebContentClient::handle(const Messages::WebContentClient::DidChangeSelection&)
 {
 #ifdef DEBUG_SPAM
-    dbg() << "handle: WebContentClient::DidChangeSelection!";
+    dbgln("handle: WebContentClient::DidChangeSelection!");
 #endif
     m_view.notify_server_did_change_selection({});
 }
@@ -110,7 +110,7 @@ void WebContentClient::handle(const Messages::WebContentClient::DidHoverLink& me
 void WebContentClient::handle(const Messages::WebContentClient::DidUnhoverLink&)
 {
 #ifdef DEBUG_SPAM
-    dbg() << "handle: WebContentClient::DidUnhoverLink!";
+    dbgln("handle: WebContentClient::DidUnhoverLink!");
 #endif
     m_view.notify_server_did_unhover_link({});
 }