Fix DHCECK when URL is not valid.

This was introduced in https://crrev.com/c/5356198.  A a URL check was
removed because it was assumed the last committed URL is always valid.
However, depending on the state of the WebContents this is not always
the case.

Bug: b/328262616, b/329444366
Change-Id: I414a9eb5cd945cd526d0da45a7dffb34b09c29e4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5402024
Reviewed-by: Nasser Al-shawwa <alshawwa@chromium.org>
Commit-Queue: Nasser Al-shawwa <alshawwa@chromium.org>
Auto-Submit: Roger Tawa <rogerta@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1279310}
diff --git a/chrome/browser/enterprise/data_protection/data_protection_navigation_observer.cc b/chrome/browser/enterprise/data_protection/data_protection_navigation_observer.cc
index 40a2897..24d50e7 100644
--- a/chrome/browser/enterprise/data_protection/data_protection_navigation_observer.cc
+++ b/chrome/browser/enterprise/data_protection/data_protection_navigation_observer.cc
@@ -82,7 +82,7 @@
 }
 
 bool SkipUrl(const GURL& url) {
-  return url.SchemeIs(content::kChromeUIScheme) ||
+  return !url.is_valid() || url.SchemeIs(content::kChromeUIScheme) ||
          url.SchemeIs(extensions::kExtensionScheme);
 }