Launch packaged app with files on Drive on Chrome OS.

webkit/fileapi/file_system_context.cc

Index: webkit/fileapi/file_system_context.cc
diff --git a/webkit/fileapi/file_system_context.cc b/webkit/fileapi/file_system_context.cc
index 017cf29f417ed78b3a73a84a6a864fdbf0f909b5..383b1577a1fdc536e9bb149874b82d62c40e9898 100644
--- a/webkit/fileapi/file_system_context.cc
+++ b/webkit/fileapi/file_system_context.cc
@@ -141,6 +141,7 @@ FileSystemMountPointProvider* FileSystemContext::GetMountPointProvider(
     case kFileSystemTypeSyncable:
       return sandbox_provider_.get();
     case kFileSystemTypeExternal:
+    case kFileSystemTypeExternalFullPath:
     case kFileSystemTypeDrive:
     case kFileSystemTypeRestrictedNativeLocal:
       return external_provider_.get();
@@ -349,20 +350,26 @@ FileSystemURL FileSystemContext::CrackFileSystemURL(
 
   // The returned value in case there is no crackers which can crack the url.
   // This is valid situation for non isolated/external file systems.
-  FileSystemURL result = url;
-
-  for (size_t i = 0; i < url_crackers_.size(); ++i) {
-    if (!url_crackers_[i]->HandlesFileSystemMountType(url.type()))
-      continue;
-
-    result = url_crackers_[i]->CreateCrackedFileSystemURL(url.origin(),
-                                                          url.type(),
-                                                          url.path());
-    if (result.is_valid())
-      return result;
+  FileSystemURL current = url;
+
+  // File system may be mounted multiple times (e.g., an isolated filesystem on
+  // top of an external filesystem). Hence cracking needs to be iterated.
+  for (;;) {
+    FileSystemURL cracked = current;
+    bool crack_happened = false;
+    for (size_t i = 0; i < url_crackers_.size(); ++i) {
+      if (!url_crackers_[i]->HandlesFileSystemMountType(current.type()))
+        continue;
+      crack_happened = true;
+      cracked = url_crackers_[i]->CrackFileSystemURL(current);
+      if (cracked.is_valid())
+        break;
+    }
+    if (!crack_happened)

[kinuko, 2013/03/19 20:34:50]

nit: if (cracked == current) may be enough

[kinaba, 2013/03/21 07:35:13]

Done.

+      break;
+    current = cracked;
   }
-
-  return result;
+  return current;
 }
 
 FileSystemFileUtil* FileSystemContext::GetFileUtil(