clear all caches when errors occur
clear all caches when errors occur

Change-Id: I5fdaeafca4743dc7fe2efe49c8c5e48a5fbab5f7
Reviewed-on: http://cr.qtquick.me/535
Tested-by: http://ci.qtquick.me/
Tested-by: Tasuku Suzuki <42980d970444f9101663582e70cd53623b3238b4@gmail.com>
Reviewed-by: Tasuku Suzuki <42980d970444f9101663582e70cd53623b3238b4@gmail.com>

yatsek/silk,qt-users-jp/silk,qt-users-jp/silk,qt-users-jp/silk,yatsek/silk,qt-users-jp/silk,yatsek/silk,yatsek/silk