Revert "Reland "Extension content verification: unify "is from store" logic""

This reverts commit 7cd54377.

Reason for revert: https://bugs.chromium.org/p/chromium/issues/detail?id=770001: PrefHashBrowserTestUnchangedCustomInstance browser_tests are failing on "Linux64/Win32&64/Mac64 - trunk" 

Original change's description:
> Reland "Extension content verification: unify "is from store" logic"
> 
> (Not a direct reland: the change to extension_settings_browsertest.h
> was not in the original CL)
> 
> This is a reland of f3bd7c65
> Original change's description:
> > Extension content verification: unify "is from store" logic
> > 
> > Bug: 766806
> > Change-Id: I1a210ded77cc9ffdc0039fca097c6fdba7ff0131
> > Reviewed-on: https://chromium-review.googlesource.com/677403
> > Commit-Queue: proberge <proberge@chromium.org>
> > Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#505092}
> 
> Bug: 766806
> Change-Id: I4a0c69c50d7bc41a47e264ad9b9e3136a729ec96
> Reviewed-on: https://chromium-review.googlesource.com/698985
> Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
> Commit-Queue: proberge <proberge@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#506422}

TBR=lazyboy@chromium.org,rdevlin.cronin@chromium.org,proberge@chromium.org

Change-Id: I55c8e8de6077788b1833457f660aca9299710815
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 766806
Reviewed-on: https://chromium-review.googlesource.com/701318Reviewed-by: proberge <proberge@chromium.org>
Commit-Queue: proberge <proberge@chromium.org>
Cr-Commit-Position: refs/heads/master@{#506612}

chrome/browser/extensions/chrome_content_verifier_delegate.cc

@@ -21,7 +21,6 @@
 #include "base/version.h"
 #include "build/build_config.h"
 #include "chrome/browser/extensions/extension_service.h"
-#include "chrome/browser/extensions/install_verifier.h"
 #include "chrome/browser/extensions/policy_extension_reinstaller.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/extension_constants.h"
@@ -131,10 +130,7 @@ ContentVerifierDelegate::Mode ChromeContentVerifierDelegate::ShouldBeVerified(
   if (!Manifest::IsAutoUpdateableLocation(extension.location()))
     return ContentVerifierDelegate::NONE;
 
-  // Use the InstallVerifier's |IsFromStore| method to avoid discrepancies
-  // between which extensions are considered in-store.
-  // See https://crbug.com/766806 for details.
-  if (!InstallVerifier::IsFromStore(extension)) {
+  if (!ManifestURL::UpdatesFromGallery(&extension)) {
     // It's possible that the webstore update url was overridden for testing
     // so also consider extensions with the default (production) update url
     // to be from the store as well.

chrome/browser/ui/webui/extensions/extension_settings_browsertest.h

@@ -10,7 +10,6 @@
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "chrome/test/base/web_ui_browser_test.h"
-#include "extensions/browser/scoped_ignore_content_verifier_for_test.h"
 #include "extensions/browser/test_management_policy.h"
 #include "extensions/common/feature_switch.h"
 
@@ -56,9 +55,6 @@ class ExtensionSettingsUIBrowserTest : public WebUIBrowserTest {
 
   base::FilePath test_data_dir_;
 
-  // Disable extension content verification.
-  extensions::ScopedIgnoreContentVerifierForTest ignore_content_verification_;
-
   // Used to enable the error console.
   std::unique_ptr<extensions::FeatureSwitch::ScopedOverride>
       error_console_override_;