LibWebView: Protect URL highlighting against partially-typed URLs

The current helpers assume that a valid URL is a full URL (i.e. contains
the "://" separator between the scheme and domain). This isn't true, as
"file:" alone is parsed as a valid URL.

We must also avoid simply searching for the parsed public suffix in the
original URL string. For example, "com" is a public suffix. If we search
for that in the URL "com.com", we will think the public suffix starts at
index 0.

Meta/Lagom/CMakeLists.txt

@@ -651,6 +651,7 @@ if (BUILD_LAGOM)
             LibTimeZone
             LibUnicode
             LibVideo
+            LibWebView
             LibXML
         )
         if (ENABLE_LAGOM_LIBWEB)