embedded newline in Python code causes next line indent to be wrong

[hayne]

Issue Type: Bug

If there is an embedded (explicit) newline in a string in a Python statement,
the auto-indent of the next line is wrong.
Example:
print("aaa\nbbb")
Pressing return/enter after the above line causes the indent to be several spaces in from the left margin.
This doesn't happen with the following statement where the newline is replaced by a space:
print("aaa bbb")

Extension version: 2019.2.5558
VS Code version: Code 1.32.3 (a3db5be9b5c6ba46bb7555ec5d60178ecc2eaae4, 2019-03-14T22:46:48.547Z)
OS version: Darwin x64 18.2.0

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-6820HQ CPU @ 2.70GHz (8 x 2700)
GPU Status	2d_canvas: enabled checker_imaging: disabled_off flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled multiple_raster_threads: enabled_on native_gpu_memory_buffers: enabled rasterization: enabled surface_synchronization: enabled_on video_decode: enabled webgl: enabled webgl2: enabled
Load (avg)	2, 2, 2
Memory (System)	16.00GB (2.54GB free)
Process Argv	-psn_0_4178940
Screen Reader	no
VM	0%

[DonJayamanne]

Duplicate of #4563