Reland of Change extension icon load errors to warnings

extensions/common/manifest_handler_helpers.cc

 // Copyright 2014 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 "extensions/common/manifest_handler_helpers.h"
 
 #include <stddef.h>
 
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "extensions/common/error_utils.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/extension_icon_set.h"
+#include "extensions/common/file_util.h"
 #include "extensions/common/manifest_constants.h"
+#include "grit/extensions_strings.h"
+#include "ui/base/l10n/l10n_util.h"
 
 namespace extensions {
 
 namespace errors = manifest_errors;
 
 namespace manifest_handler_helpers {
 
 bool NormalizeAndValidatePath(std::string* path) {
   size_t first_non_slash = path->find_first_not_of('/');
   if (first_non_slash == std::string::npos) {
     *path = "";
     return false;
   }
 
   *path = path->substr(first_non_slash);
   return true;
 }
 
-bool LoadIconsFromDictionary(const base::DictionaryValue* icons_value,
+bool LoadIconsFromDictionary(Extension* extension,
+                             const base::DictionaryValue* icons_value,
                              ExtensionIconSet* icons,
                              base::string16* error) {
   DCHECK(icons);
   DCHECK(error);
   for (base::DictionaryValue::Iterator iterator(*icons_value);
        !iterator.IsAtEnd(); iterator.Advance()) {
     int size = 0;
     std::string icon_path;
     if (!base::StringToInt(iterator.key(), &size) ||
         !iterator.value().GetAsString(&icon_path) ||
         !NormalizeAndValidatePath(&icon_path)) {
       *error = ErrorUtils::FormatErrorMessageUTF16(errors::kInvalidIconPath,
                                                    iterator.key());
       return false;
     }
 
-    icons->Add(size, icon_path);
+    // For backwards compatibility, only warn (don't error out) if an icon is
+    // missing. Component extensions can skip this check as their icons are not
+    // located on disk. Unpacked extensions skip this check and fail later
+    // during validation if the file isn't present. See crbug.com/570249
+    // TODO(estade|devlin): remove this workaround and let install fail in the
+    // validate step a few releases after M49. See http://crbug.com/571193
+    if (Manifest::IsComponentLocation(extension->location()) ||
+        Manifest::IsUnpackedLocation(extension->location()) ||
+        file_util::ValidateFilePath(
+            extension->GetResource(icon_path).GetFilePath())) {
+      icons->Add(size, icon_path);
+    } else {
+      extension->AddInstallWarning(InstallWarning(
+          l10n_util::GetStringFUTF8(IDS_EXTENSION_LOAD_ICON_FAILED,
+                                    base::UTF8ToUTF16(icon_path)),
+          std::string()));
+    }
   }
   return true;
 }
 
 }  // namespace manifest_handler_helpers
 
 }  // namespace extensions