[Extensions] Code Cleanup - Remove redundant smart-ptr get()s

Given std::unique_ptr<T> t, t.get()-> is the same as t->.
Similarly, *t.get() is the same as *t. Simplify extensions
code to conform.

Generated with clang-tidy.
See https://chromium.googlesource.com/chromium/src/+/master/docs/clang_tidy.md

BUG=None

Review-Url: https://codereview.chromium.org/2152373003
Cr-Commit-Position: refs/heads/master@{#406117}
diff --git a/chrome/browser/extensions/extension_service_unittest.cc b/chrome/browser/extensions/extension_service_unittest.cc
index 7cdb68c..6c385fc 100644
--- a/chrome/browser/extensions/extension_service_unittest.cc
+++ b/chrome/browser/extensions/extension_service_unittest.cc
@@ -640,7 +640,7 @@
     std::unique_ptr<extensions::ExtensionSet> all_unblocked_extensions =
         registry()->GenerateInstalledExtensionsSet(
             ExtensionRegistry::EVERYTHING & ~ExtensionRegistry::BLOCKED);
-    if (all_unblocked_extensions.get()->Contains(id))
+    if (all_unblocked_extensions->Contains(id))
       return testing::AssertionFailure() << id << " is still unblocked!";
     if (!registry()->blocked_extensions().Contains(id))
       return testing::AssertionFailure() << id << " is not blocked!";