Implementing Repeated Start on an STM32 F0 I2C Slave
I finally got a response from ST. There is no reference to Repeated Start Condition in the F0 documentation nor the F0 HAL examples but there is an example in the L4 firmware packge:

In L4 Firmware repository, look under 
STM32Cube_FW_L4_V1.8.0\Projects\STM32L496ZG-
Nucleo\Examples\I2C\I2C_TwoBoards_RestartComIT

The example shows how to perform a single I2C data buffer TX/RX in Interrupt Mode and with a Repeated Start condition.