Remove some uses of stl_util's STLDeleteContainerPointers.

content/public/test/test_navigation_observer.cc

Index: content/public/test/test_navigation_observer.cc
diff --git a/content/public/test/test_navigation_observer.cc b/content/public/test/test_navigation_observer.cc
index b8a57a20c2a9a50b4c8014b27669c274170424a4..684c66f91e9f5894967aa76c8f236f59b0a76e4a 100644
--- a/content/public/test/test_navigation_observer.cc
+++ b/content/public/test/test_navigation_observer.cc
@@ -6,9 +6,9 @@
 
 #include "base/bind.h"
 #include "base/macros.h"
+#include "base/memory/ptr_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
-#include "base/stl_util.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -109,9 +109,6 @@ TestNavigationObserver::TestNavigationObserver(
 
 TestNavigationObserver::~TestNavigationObserver() {
   StopWatchingNewWebContents();
-
-  base::STLDeleteContainerPointers(web_contents_observers_.begin(),
-                                   web_contents_observers_.end());
 }
 
 void TestNavigationObserver::Wait() {
@@ -130,7 +127,7 @@ void TestNavigationObserver::StopWatchingNewWebContents() {
 
 void TestNavigationObserver::RegisterAsObserver(WebContents* web_contents) {
   web_contents_observers_.insert(
-      new TestWebContentsObserver(this, web_contents));
+      base::MakeUnique<TestWebContentsObserver>(this, web_contents));
 }
 
 void TestNavigationObserver::OnWebContentsCreated(WebContents* web_contents) {
@@ -140,8 +137,11 @@ void TestNavigationObserver::OnWebContentsCreated(WebContents* web_contents) {
 void TestNavigationObserver::OnWebContentsDestroyed(
     TestWebContentsObserver* observer,
     WebContents* web_contents) {
-  web_contents_observers_.erase(observer);
-  delete observer;
+  web_contents_observers_.erase(std::find_if(
+      web_contents_observers_.begin(), web_contents_observers_.end(),
+      [observer](const std::unique_ptr<TestWebContentsObserver>& ptr) {
+        return ptr.get() == observer;
+      }));
 }
 
 void TestNavigationObserver::OnNavigationEntryCommitted(