Add support for directory access to the file system API.

chrome/browser/extensions/api/file_handlers/app_file_handler_util.cc

Index: chrome/browser/extensions/api/file_handlers/app_file_handler_util.cc
diff --git a/chrome/browser/extensions/api/file_handlers/app_file_handler_util.cc b/chrome/browser/extensions/api/file_handlers/app_file_handler_util.cc
index 64c81728b2520a0694dba4b772d2ed684739db2a..becb9d925fe0f28c5497f61a431f3acbe5d92353 100644
--- a/chrome/browser/extensions/api/file_handlers/app_file_handler_util.cc
+++ b/chrome/browser/extensions/api/file_handlers/app_file_handler_util.cc
@@ -64,6 +64,9 @@ bool DoCheckWritableFile(const base::FilePath& path) {
   if (base::PathExists(path) && file_util::IsLink(path))
     return false;
 
+  if (base::DirectoryExists(path))
+    return base::PathIsWritable(path);

[Matt Giuca, 2013/08/27 04:30:53]

Do you handle the case of trying to write to a file that is actually a
directory, and vice versa?

(More generally, do you handle the case where you retain access to a file or
directory, then in between sessions, the file changes to a directory or vice
versa?)

[Sam McNally, 2013/08/27 05:16:37]

That would cause getFile/getDirectory to fail in the custom bindings.

+
   // Create the file if it doesn't already exist.
   base::PlatformFileError error = base::PLATFORM_FILE_OK;
   int creation_flags = base::PLATFORM_FILE_CREATE |
@@ -290,7 +293,8 @@ GrantedFileEntry CreateFileEntry(
     Profile* profile,
     const Extension* extension,
     int renderer_id,
-    const base::FilePath& path) {
+    const base::FilePath& path,
+    bool is_directory) {
   GrantedFileEntry result;
   fileapi::IsolatedContext* isolated_context =
       fileapi::IsolatedContext::GetInstance();
@@ -303,8 +307,11 @@ GrantedFileEntry CreateFileEntry(
   content::ChildProcessSecurityPolicy* policy =
       content::ChildProcessSecurityPolicy::GetInstance();
   policy->GrantReadFileSystem(renderer_id, result.filesystem_id);
-  if (HasFileSystemWritePermission(extension))
+  if (HasFileSystemWritePermission(extension)) {
     policy->GrantWriteFileSystem(renderer_id, result.filesystem_id);
+    if (is_directory)
+      policy->GrantCreateFileForFileSystem(renderer_id, result.filesystem_id);
+  }
 
   result.id = result.filesystem_id + ":" + result.registered_name;
   return result;
@@ -320,6 +327,8 @@ void CheckWritableFiles(
   checker->Check();
 }
 
+GrantedFileEntry::GrantedFileEntry() {}
+
 bool HasFileSystemWritePermission(const Extension* extension) {
   return extension->HasAPIPermission(APIPermission::kFileSystemWrite);
 }