Are there currently any planned or proposed missions to measure the gravitational fields of other planets in our solar system? I just recently found out about the GRACE Nasa mission which basically mapped out the gravitational anomalies of earth as well as serving extensively in the study of earths geology and the movement of its distribution of water. While I continued reading about it I came across GRAIL which did a similar job but over our moon. 

Link here to learn about GRACE: GRACE

Here for GRAIL: GRAIL

What i'm now wondering is are there space agencies or organizations considering missions to any of the other planets in our solar system and attempting to measure their gravitational anomalies in a similar manner hopefully giving vital information on their inner structure or formation.
There are no such missions in an advanced state of planning, however we do have a good idea of the gravity field around Mars, gleaned from observations of anomalies in the orbits of the various orbital probes.

These data were gathered into a map of the gravity field of Mars

According to that NASA article:


  The map was derived using Doppler and range tracking data collected by NASA's Deep Space Network from three NASA spacecraft in orbit around Mars: Mars Global Surveyor (MGS), Mars Odyssey (ODY), and the Mars Reconnaissance Orbiter (MRO). 


The research is published as Antonio Genova et al. 2016, Seasonal and static gravity field of Mars from MGS, Mars Odyssey and MRO radio science, Icarus, vol. 272, pp. 228-245; doi: 10.1016/j.icarus.2016.02.050



In addition, the Cassini Spacecraft has made detailed gravitational measurements of Saturn and and along with imaging, internal structure details of its moon Enceladus. Also the Juno Spacecraft has made detailed measurements of Jupiter's internal structure via maps of it's gravity field as well.