Fix for Bug 50726 "Save extension list and "winning" prefs from extensions"

chrome/browser/extensions/test_extension_prefs.cc

Index: chrome/browser/extensions/test_extension_prefs.cc
diff --git a/chrome/browser/extensions/test_extension_prefs.cc b/chrome/browser/extensions/test_extension_prefs.cc
index 2cbb2d16857e1db7e58a60001988a81f1d76913d..dc255168ec209796397648f80125091dd023e160 100644
--- a/chrome/browser/extensions/test_extension_prefs.cc
+++ b/chrome/browser/extensions/test_extension_prefs.cc
@@ -10,14 +10,75 @@
 #include "base/values.h"
 #include "chrome/browser/browser_thread.h"
 #include "chrome/browser/extensions/extension_prefs.h"
+#include "chrome/browser/extensions/extension_pref_store.h"
+#include "chrome/browser/prefs/browser_prefs.h"
+#include "chrome/browser/prefs/dummy_pref_store.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/prefs/pref_value_store.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/common/json_pref_store.h"
+#include "chrome/test/testing_pref_service.h"
+#include "chrome/test/testing_profile.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
-TestExtensionPrefs::TestExtensionPrefs() {
+// Mock ExtensionPrefs class with artificial clock to guarantee that no two
+// extensions get the same installation time stamp and we can reliably
+// assert the installation order in the tests below.
+class MockExtensionPrefs : public ExtensionPrefs {
+ public:
+  MockExtensionPrefs(Profile* profile,
+                     const FilePath& root_dir_)
+    : ExtensionPrefs(profile, root_dir_),
+      currentTime(base::Time::Now())
+  {}
+  ~MockExtensionPrefs() {}
+
+ protected:
+  mutable base::Time currentTime;
+
+  virtual base::Time GetCurrentTime() const {
+    currentTime += base::TimeDelta::FromSeconds(10);
+    return currentTime;
+  }
+};
+
+class TestingProfileWithFixedPath : public TestingProfile {
+ public:
+  explicit TestingProfileWithFixedPath(const FilePath& path) : path_(path) {}
+  virtual ~TestingProfileWithFixedPath() {}
+
+  virtual void CreateTestingPrefService() {
+    DCHECK(!prefs_.get());
+    PrefStore* managed_platform_prefs = new DummyPrefStore();
+    PrefStore* device_management_prefs = new DummyPrefStore();
+    PrefStore* extension_prefs = new ExtensionPrefStore(this);
+    PrefStore* command_line_prefs = NULL;
+    PrefStore* user_prefs = new JsonPrefStore(
+        path_.AppendASCII("Preferences"),
+        BrowserThread::GetMessageLoopProxyForThread(BrowserThread::FILE));
+    PrefStore* recommended_prefs = NULL;
+    PrefStore* default_pref = new DummyPrefStore();
+    testing_prefs_ = new TestingPrefService(managed_platform_prefs,
+                                            device_management_prefs,
+                                            extension_prefs,
+                                            command_line_prefs,
+                                            user_prefs,
+                                            recommended_prefs,
+                                            default_pref);
+    prefs_.reset(testing_prefs_);
+    Profile::RegisterUserPrefs(prefs_.get());
+    browser::RegisterAllPrefs(prefs_.get(), prefs_.get());
+  }
+
+  virtual FilePath GetPath() {
+    return path_;
+  }
+ private:
+  FilePath path_;
+};
+
+TestExtensionPrefs::TestExtensionPrefs() : pref_service_(NULL) {
   EXPECT_TRUE(temp_dir_.CreateUniqueTempDir());
   preferences_file_ = temp_dir_.path().AppendASCII("Preferences");
   extensions_dir_ = temp_dir_.path().AppendASCII("Extensions");
@@ -29,7 +90,10 @@ TestExtensionPrefs::TestExtensionPrefs() {
 TestExtensionPrefs::~TestExtensionPrefs() {}
 
 void TestExtensionPrefs::RecreateExtensionPrefs() {
-  if (pref_service_.get()) {
+  // We persist and reload the PrefService's PrefStores because this process
+  // deletes all empty dictionaries. The ExtensionPrefs implementation
+  // needs to be able to handle this situation.
+  if (pref_service_) {
     // The PrefService writes its persistent file on the file thread, so we
     // need to wait for any pending I/O to complete before creating a new
     // PrefService.
@@ -39,10 +103,10 @@ void TestExtensionPrefs::RecreateExtensionPrefs() {
     file_loop.RunAllPending();
   }
 
-  // Create a |PrefService| instance that contains only user defined values.
-  pref_service_.reset(PrefService::CreateUserPrefService(preferences_file_));
-  ExtensionPrefs::RegisterUserPrefs(pref_service_.get());
-  prefs_.reset(new ExtensionPrefs(pref_service_.get(), temp_dir_.path()));
+  profile_.reset(new TestingProfileWithFixedPath(temp_dir_.path()));
+  pref_service_ = profile_->GetPrefs();
+  prefs_.reset(new MockExtensionPrefs(profile_.get(),
+                                      temp_dir_.path()));
 }
 
 scoped_refptr<Extension> TestExtensionPrefs::AddExtension(std::string name) {