[WIP] make GURL::path() return a StringPiece

components/history/core/browser/top_sites_cache.cc

Index: components/history/core/browser/top_sites_cache.cc
diff --git a/components/history/core/browser/top_sites_cache.cc b/components/history/core/browser/top_sites_cache.cc
index c436e68cb0e73871d5f41e1131f0a1f2bfd23801..20fb227e528c3822d6db46c3b13b906167ca8143 100644
--- a/components/history/core/browser/top_sites_cache.cc
+++ b/components/history/core/browser/top_sites_cache.cc
@@ -93,7 +93,8 @@ GURL TopSitesCache::GetGeneralizedCanonicalURL(const GURL& url) const {
     return GURL::EmptyGURL();
   GURL compare_url_lo(GetURLFromIterator(it_lo));
   if (!HaveSameSchemeHostAndPort(base_url, compare_url_lo) ||
-      !IsPathPrefix(base_url.path(), compare_url_lo.path())) {
+      !IsPathPrefix(base_url.path().as_string(),
+                    compare_url_lo.path().as_string())) {
     return GURL::EmptyGURL();
   }
   // Everything before |it_lo| is irrelevant.
@@ -104,7 +105,7 @@ GURL TopSitesCache::GetGeneralizedCanonicalURL(const GURL& url) const {
     --it;
     GURL compare_url(GetURLFromIterator(it));
     DCHECK(HaveSameSchemeHostAndPort(compare_url, url));
-    if (IsPathPrefix(compare_url.path(), url.path()))
+    if (IsPathPrefix(compare_url.path().as_string(), url.path().as_string()))
       return it->first.first->url;
   }