Fix filesystem API file_handlers to work for drive on ChromeOS.

webkit/fileapi/external_mount_points.cc

Index: webkit/fileapi/external_mount_points.cc
diff --git a/webkit/fileapi/external_mount_points.cc b/webkit/fileapi/external_mount_points.cc
index 5c84c1bb248e49456e94b1d85b2fae022b7e4d97..b53c34b859485fcbe67ba7ab4a7ec46023f02c9a 100644
--- a/webkit/fileapi/external_mount_points.cc
+++ b/webkit/fileapi/external_mount_points.cc
@@ -244,12 +244,20 @@ FileSystemURL ExternalMountPoints::CreateCrackedFileSystemURL(
                        mount_name, cracked_type, cracked_path);
 }
 
-RemoteFileSystemProxyInterface* ExternalMountPoints::GetRemoteFileSystemProxy(
-    const std::string& mount_name) const {
+RemoteFileSystemProxyInterface*
+ExternalMountPoints::GetRemoteFileSystemProxyForPath(
+    const base::FilePath& full_path) const {
   base::AutoLock locker(lock_);
-  NameToInstance::const_iterator found = instance_map_.find(mount_name);
+
+  std::string mount_point;
+  if (!GetMountPointForPath(full_path, &mount_point, NULL))
+    return NULL;
+
+  // Get mount point instance.
+  NameToInstance::const_iterator found = instance_map_.find(mount_point);
   if (found == instance_map_.end())
     return NULL;
+
   return found->second->remote_proxy();
 }
 
@@ -263,22 +271,21 @@ void ExternalMountPoints::AddMountPointInfosTo(
   }
 }
 
-bool ExternalMountPoints::GetVirtualPath(const base::FilePath& path_in,
+bool ExternalMountPoints::GetVirtualPath(const base::FilePath& path,
                                          base::FilePath* virtual_path) {
   DCHECK(virtual_path);
 
   base::AutoLock locker(lock_);
 
-  base::FilePath path = NormalizeFilePath(path_in);
-  std::map<base::FilePath, std::string>::reverse_iterator iter(
-      path_to_name_map_.upper_bound(path));
-  if (iter == path_to_name_map_.rend())
+  std::string mount_point_name;
+  base::FilePath mount_point_root;
+  if (!GetMountPointForPath(path, &mount_point_name, &mount_point_root))
     return false;
 
-  *virtual_path = CreateVirtualRootPath(iter->second);
-  if (iter->first == path)
+  *virtual_path = CreateVirtualRootPath(mount_point_name);
+  if (mount_point_root == path)
     return true;
-  return iter->first.AppendRelativePath(path, virtual_path);
+  return mount_point_root.AppendRelativePath(path, virtual_path);
 }
 
 base::FilePath ExternalMountPoints::CreateVirtualRootPath(
@@ -332,6 +339,31 @@ bool ExternalMountPoints::ValidateNewMountPoint(const std::string& mount_name,
          !path.IsParent(potential_child->first);
 }
 
+bool ExternalMountPoints::GetMountPointForPath(
+    const base::FilePath& path,
+    std::string* mount_point_name,
+    base::FilePath* mount_point_root) const {
+  DCHECK(mount_point_name);
+
+  // Get mount point the path belongs to. It is the path whose value is smaller
+  // than normalized path, but also parents the normalized_path. Note that
+  // ExternalMountPoints are constrained so there cannot be a root path x for
+  // which the following holds: root_path(path) < x < path.
+  base::FilePath normalized_path = NormalizeFilePath(path);
+  std::map<base::FilePath, std::string>::const_reverse_iterator iter(
+      path_to_name_map_.upper_bound(normalized_path));
+  if (iter == path_to_name_map_.rend() ||
+      (iter->first != normalized_path &&
+       !iter->first.IsParent(normalized_path))) {
+    return false;
+  }
+
+  *mount_point_name = iter->second;
+  if (mount_point_root)
+    *mount_point_root = iter->first;
+  return true;
+}
+
 ScopedExternalFileSystem::ScopedExternalFileSystem(
     const std::string& mount_name,
     FileSystemType type,