Make isolated file system works for a device root (e.g. X:\\)

chrome/browser/extensions/api/file_system/file_system_api.cc

Index: chrome/browser/extensions/api/file_system/file_system_api.cc
diff --git a/chrome/browser/extensions/api/file_system/file_system_api.cc b/chrome/browser/extensions/api/file_system/file_system_api.cc
index d70eea3cd5feda788bd7bec34a7e616e99e31873..3802eea3f44cc414767ee85c2bc734800eee7f15 100644
--- a/chrome/browser/extensions/api/file_system/file_system_api.cc
+++ b/chrome/browser/extensions/api/file_system/file_system_api.cc
@@ -19,6 +19,8 @@
 #include "webkit/fileapi/file_system_util.h"
 #include "webkit/fileapi/isolated_context.h"
 
+using fileapi::IsolatedContext;
+
 const char kInvalidParameters[] = "Invalid parameters";
 const char kSecurityError[] = "Security error";
 const char kInvalidCallingPage[] = "Invalid calling page";
@@ -56,10 +58,10 @@ bool GetFilePathOfFileEntry(const std::string& filesystem_name,
     return false;
   }
 
-  fileapi::IsolatedContext* context = fileapi::IsolatedContext::GetInstance();
+  IsolatedContext* context = IsolatedContext::GetInstance();
   FilePath relative_path = FilePath::FromUTF8Unsafe(filesystem_path);
-  FilePath virtual_path = context->CreateVirtualPath(filesystem_id,
-                                                     relative_path);
+  FilePath virtual_path = context->CreateVirtualRootPath(filesystem_id)
+      .Append(relative_path);
   if (!context->CrackIsolatedPath(virtual_path,
                                   &filesystem_id,
                                   NULL,
@@ -252,14 +254,13 @@ void FileSystemPickerFunction::CheckWritableFile(const FilePath& path) {
 void FileSystemPickerFunction::RegisterFileSystemAndSendResponse(
     const FilePath& path, bool for_save) {
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
-  std::set<FilePath> filesets;
-  filesets.insert(path);
 
-  fileapi::IsolatedContext* isolated_context =
-      fileapi::IsolatedContext::GetInstance();
+  IsolatedContext* isolated_context = IsolatedContext::GetInstance();
+  std::string file_name = IsolatedContext::GetNameForPath(path);
+
   DCHECK(isolated_context);
-  std::string filesystem_id = isolated_context->RegisterIsolatedFileSystem(
-      filesets);
+  std::string filesystem_id = isolated_context->RegisterFileSystemForFile(
+      file_name, path);
 
   content::ChildProcessSecurityPolicy* policy =
       content::ChildProcessSecurityPolicy::GetInstance();
@@ -278,7 +279,7 @@ void FileSystemPickerFunction::RegisterFileSystemAndSendResponse(
   DictionaryValue* dict = new DictionaryValue();
   result_.reset(dict);
   dict->SetString("fileSystemId", filesystem_id);
-  dict->SetString("baseName", path.BaseName().AsUTF8Unsafe());
+  dict->SetString("baseName", file_name);
   SendResponse(true);
 }