Revert 288017 "Parse Drive API responses all at once in the bloc..."

Revert 288017 "Parse Drive API responses all at once in the bloc..."

It broke Drive sync completely.

> Parse Drive API responses all at once in the blocking pool.
> 
> Previous implementation did the parsing of string to base::Value
> on blocking pool, and that of base::Value to specific data types
> either on UI thread or on yet another post to blocking pool.
> 
> The previous implementation is slightly inefficient and moreover
> involves a subtle bug 284244.
> 
> BUG=284244
> 
> Review URL: https://codereview.chromium.org/442193002

TBR=kinaba@chromium.org
BUG=401843
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=288216

[kinaba, 2014-08-08 03:38:25]

Committed patchset #1 manually as r288216 (tree was closed).