Add the Windows.IsPinnedToTaskbar metric.

chrome/utility/shell_handler_impl_win.cc

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/utility/shell_handler_impl_win.h"
+
+#include <shldisp.h>
+
+#include "base/files/file_enumerator.h"
+#include "base/files/file_path.h"
+#include "base/path_service.h"
+#include "base/scoped_native_library.h"
+#include "base/win/scoped_bstr.h"
+#include "base/win/scoped_com_initializer.h"
+#include "base/win/scoped_comptr.h"
+#include "base/win/scoped_variant.h"
+#include "base/win/shortcut.h"
+#include "chrome/installer/util/install_util.h"
+#include "content/public/utility/utility_thread.h"
+
+namespace {
+
+// This class checks if the current executable is pinned to the taskbar. It also
+// keeps track of the errors that occurs that prevents it from getting a result.
+class IsPinnedToTaskbarHelper {
+ public:
+  IsPinnedToTaskbarHelper() = default;
+  ~IsPinnedToTaskbarHelper() = default;
+
+  // Returns true if the current executable is pinned to the taskbar.
+  bool GetResult();
+  bool error_occured() { return error_occured_; }

[gab, 2016/06/28 20:59:18]

nit: Empty line above

[Patrick Monette, 2016/06/28 23:22:24]

Done.

+
+ private:
+  // Returns the shell resource string identified by |resource_id|, or an empty
+  // string on error.
+  base::string16 LoadShellResourceString(uint32_t resource_id);
+
+  // Returns true if the "Unpin from taskbar" verb is available for |shortcut|,
+  // which means that the shortcut is pinned to the taskbar.
+  bool ShortcutHasUnpinToTaskbarVerb(const base::FilePath& shortcut);
+
+  // Returns true if the target parameter of the |shortcut| evaluates to
+  // |program_compare|.
+  bool IsShortcutForProgram(const base::FilePath& shortcut,
+                            const InstallUtil::ProgramCompare& program_compare);
+
+  // Returns true if one of the shortcut inside the given |directory| evaluates
+  // to |program_compare| and is pinned to the taskbar.
+  bool DirectoryContainsPinnedShortcutForProgram(
+      const base::FilePath& directory,
+      const InstallUtil::ProgramCompare& program_compare);
+
+  bool error_occured_ = false;
+  base::win::ScopedCOMInitializer scoped_com_initializer_;
+};
+
+base::string16 IsPinnedToTaskbarHelper::LoadShellResourceString(

[gab, 2016/06/28 20:59:18]

Note: glanced over the code below but didn't fully re-review as I recall
reviewing in detail in earlier patch sets before it moved here and now assume
everything's been addressed (and more under grt's scrutiny :-)).

[Patrick Monette, 2016/06/28 23:22:25]

Sounds good but maybe you could review everything that touches "error_occured_"
that I added in the last patch set. 

[gab, 2016/06/30 15:28:11]

error_occurred_ lgtm

+    uint32_t resource_id) {
+  base::ScopedNativeLibrary scoped_native_library(::LoadLibraryEx(
+      FILE_PATH_LITERAL("shell32.dll"), nullptr, LOAD_LIBRARY_AS_DATAFILE));
+  if (!scoped_native_library.is_valid())
+    return base::string16();
+
+  const wchar_t* resource_ptr = nullptr;
+  int length = ::LoadStringW(scoped_native_library.get(), resource_id,
+                             reinterpret_cast<wchar_t*>(&resource_ptr), 0);
+  if (!length || !resource_ptr)
+    return base::string16();
+  return base::string16(resource_ptr, length);
+}
+
+bool IsPinnedToTaskbarHelper::ShortcutHasUnpinToTaskbarVerb(
+    const base::FilePath& shortcut) {
+  // Found inside shell32.dll's resources.
+  constexpr uint32_t kUnpinFromTaskbarID = 5387;
+
+  base::string16 verb_name(LoadShellResourceString(kUnpinFromTaskbarID));
+  if (verb_name.empty()) {
+    error_occured_ = true;
+    return false;
+  }
+
+  base::win::ScopedComPtr<IShellDispatch> shell_dispatch;
+  HRESULT hresult =
+      shell_dispatch.CreateInstance(CLSID_Shell, nullptr, CLSCTX_INPROC_SERVER);
+  if (FAILED(hresult) || !shell_dispatch) {
+    error_occured_ = true;
+    return false;
+  }
+
+  base::win::ScopedComPtr<Folder> folder;
+  hresult = shell_dispatch->NameSpace(
+      base::win::ScopedVariant(shortcut.DirName().value().c_str()),
+      folder.Receive());
+  if (FAILED(hresult) || !folder) {
+    error_occured_ = true;
+    return false;
+  }
+
+  base::win::ScopedComPtr<FolderItem> item;
+  hresult = folder->ParseName(
+      base::win::ScopedBstr(shortcut.BaseName().value().c_str()),
+      item.Receive());
+  if (FAILED(hresult) || !item) {
+    error_occured_ = true;
+    return false;
+  }
+
+  base::win::ScopedComPtr<FolderItemVerbs> verbs;
+  hresult = item->Verbs(verbs.Receive());
+  if (FAILED(hresult) || !verbs) {
+    error_occured_ = true;
+    return false;
+  }
+
+  long verb_count = 0;
+  hresult = verbs->get_Count(&verb_count);
+  if (FAILED(hresult)) {
+    error_occured_ = true;
+    return false;
+  }
+
+  long error_count = 0;
+  for (long i = 0; i < verb_count; ++i) {
+    base::win::ScopedComPtr<FolderItemVerb> verb;
+    hresult = verbs->Item(base::win::ScopedVariant(i, VT_I4), verb.Receive());
+    if (FAILED(hresult) || !verb) {
+      error_count++;
+      continue;
+    }
+    base::win::ScopedBstr name;
+    hresult = verb->get_Name(name.Receive());
+    if (FAILED(hresult)) {
+      error_count++;
+      continue;
+    }
+    if (base::StringPiece16(name, name.Length()) == verb_name)
+      return true;
+  }
+
+  if (error_count == verb_count)
+    error_occured_ = true;
+
+  return false;
+}
+
+bool IsPinnedToTaskbarHelper::IsShortcutForProgram(
+    const base::FilePath& shortcut,
+    const InstallUtil::ProgramCompare& program_compare) {
+  base::win::ShortcutProperties shortcut_properties;
+  if (!ResolveShortcutProperties(
+          shortcut, base::win::ShortcutProperties::PROPERTIES_TARGET,
+          &shortcut_properties)) {
+    return false;
+  }
+
+  return program_compare.EvaluatePath(shortcut_properties.target);
+}
+
+bool IsPinnedToTaskbarHelper::DirectoryContainsPinnedShortcutForProgram(
+    const base::FilePath& directory,
+    const InstallUtil::ProgramCompare& program_compare) {
+  base::FileEnumerator shortcut_enum(directory, false,
+                                     base::FileEnumerator::FILES);
+  for (base::FilePath shortcut = shortcut_enum.Next(); !shortcut.empty();
+       shortcut = shortcut_enum.Next()) {
+    if (IsShortcutForProgram(shortcut, program_compare) &&
+        ShortcutHasUnpinToTaskbarVerb(shortcut)) {
+      return true;
+    }
+  }
+  return false;
+}
+
+bool IsPinnedToTaskbarHelper::GetResult() {
+  base::FilePath current_exe;
+  PathService::Get(base::FILE_EXE, &current_exe);
+
+  InstallUtil::ProgramCompare current_exe_compare(current_exe);
+  // Look into the "Quick Launch\User Pinned\TaskBar" folder.
+  base::FilePath taskbar_pins_dir;
+  PathService::Get(base::DIR_TASKBAR_PINS, &taskbar_pins_dir);
+  if (DirectoryContainsPinnedShortcutForProgram(taskbar_pins_dir,
+                                                current_exe_compare)) {
+    return true;
+  }
+
+  // Check all folders in ImplicitAppShortcuts.
+  base::FilePath implicit_app_shortcuts_dir;
+  PathService::Get(base::DIR_IMPLICIT_APP_SHORTCUTS,
+                   &implicit_app_shortcuts_dir);
+  base::FileEnumerator directory_enum(implicit_app_shortcuts_dir, false,
+                                      base::FileEnumerator::DIRECTORIES);
+  for (base::FilePath directory = directory_enum.Next(); !directory.empty();
+       directory = directory_enum.Next()) {
+    if (DirectoryContainsPinnedShortcutForProgram(directory,
+                                                  current_exe_compare)) {
+      return true;
+    }
+  }
+  return false;
+}
+
+}  // namespace
+
+// static
+void ShellHandlerImpl::Create(mojom::ShellHandlerRequest request) {
+  new ShellHandlerImpl(std::move(request));
+}
+
+ShellHandlerImpl::ShellHandlerImpl(mojom::ShellHandlerRequest request)
+    : binding_(this, std::move(request)) {}
+
+ShellHandlerImpl::~ShellHandlerImpl() = default;
+
+void ShellHandlerImpl::IsPinnedToTaskbar(
+    const IsPinnedToTaskbarCallback& callback) {
+  IsPinnedToTaskbarHelper helper;
+  bool is_pinned_to_taskbar = helper.GetResult();
+  callback.Run(!helper.error_occured(), is_pinned_to_taskbar);
+}