run_target() dependencies are missing when using vs2017 generator

When running project created using run_target() from vs2017 solution it skips building targets provided by `depends` kwarg. Works on windows when using `ninja` backend.

Example project [here](https://github.com/dndanik/meson_run_target_test).

run_target() generated project file:

```xml

debug
x64



{9A0E66F0-00FC-408B-B105-C58265D47616}
x64Proj
x64
launch
10.0.16299.0




MultiByte
false
v141



<_ProjectFileVersion>10.0.30319.1
.\
launch@run\
launch



"c:\users\tester\appdata\local\programs\python\python36-32\python.exe" "c:\users\tester\appdata\local\programs\python\python36-32\lib\site-packages\mesonbuild\scripts\commandrunner.py" "F:\meson_run_target_test\build" "F:\meson_run_target_test" "" "c:\users\tester\appdata\local\programs\python\python36-32\python.exe" "C:\Users\Tester\AppData\Local\Programs\Python\Python36-32\Scripts\meson.py" "C:\Users\Tester\AppData\Local\Programs\Python\Python36-32\python.EXE" "F:\meson_run_target_test\build\launcher.py"
Running custom command.

```

Reproduce the issue with the linked example project, comparing the VS2017-generated project from run_target() with the working Ninja backend. Start by tracing run_target() and the generated XML, then verify that targets supplied through depends are built before the command runs. Done means the VS2017 generator honors those dependencies as Ninja does.

Written by the indexing model from the issue text.