[BlobAsync] Patch 4: Browser Classes & Logic.

storage/browser/blob/blob_data_builder.h

Index: storage/browser/blob/blob_data_builder.h
diff --git a/storage/browser/blob/blob_data_builder.h b/storage/browser/blob/blob_data_builder.h
index 8627ebaf3756f574e9f373fd77a4b5a3e9455d33..763afac617c5dfba63e3167e10dc89aa13c544f1 100644
--- a/storage/browser/blob/blob_data_builder.h
+++ b/storage/browser/blob/blob_data_builder.h
@@ -23,6 +23,7 @@ class Entry;
 
 namespace storage {
 class BlobStorageContext;
+class ShareableFileReference;
 
 class STORAGE_EXPORT BlobDataBuilder {
  public:
@@ -65,6 +66,21 @@ class STORAGE_EXPORT BlobDataBuilder {
                           size_t offset,
                           size_t length);
 
+  // Adds an item that is flagged for future data population. Use
+  // 'PopulateFutureFile' to set the file path and expected modification time
+  // of this file. Returns the index of the item (to be used in
+  // PopulateFutureFile). Length cannot be 0.
+  size_t AppendFutureFile(uint64_t offset, uint64_t length);
+
+  // Populates a part of an item previously allocated with AppendFutureFile.
+  // Returns true if:
+  // * The item was created by using AppendFutureFile and
+  // * The filepath is valid.
+  bool PopulateFutureFile(
+      size_t index,
+      const scoped_refptr<ShareableFileReference>& file_reference,
+      const base::Time& expected_modification_time);
+
   // You must know the length of the file, you cannot use kuint64max to specify
   // the whole file.  This method creates a ShareableFileReference to the given
   // file, which is stored in this builder.