To reproduce:
1. Create a new project with Lightweight RP template;
2. Switch platform to Android or iOS;
3. Switch color space to Linear;
4. Make sure Lightmap Encoding is set to "Low quality" (Player Settings > Other Settings > Lightmap Encoding);
5. Open the Sample Scene.

Results: the scene has red tint when Lightmap encoding is Low quality in linear color space.

Notes:
-Clearing Baked data in Lighting settings removes the red tint, after re-baking lights it's back again;
-Happens with both Subtractive and Baked Indirect modes;
-Doesn't reproduce with Normal or High quality Lightmap encoding.
-Checked Lightweight RP packages from 6.5.2 to 7.1.0, all have the same effect.

Reproduced with: 2019.3.0a10
Not reproduced with: 2019.3.0a8, 2019.3.0a9

Fixed in: 2019.3.0a12