Reproduction Steps:
1. Open User's project
2. Notice that "Splash2048x1536" is set as Standalone Virtual Reality Splash Image and no other splash images or assets are added to the iOS build
3. Build development build for iOS
4. Run App on device and attach Profiler
5. Take Sample in Detailed Memory profiler
6. Notice that "Splash2048x1536" is included into the build

Expected behaviour: Assets should not be included into the build if they are not used there
Actual results: Image set as Standalone Virtual Reality Splash Image was included into the iOS build

Reproduced on iPhone 5s iOS 9.2.1
Reproduced on versions: Unity 5.3.6p3, 5.4.0f2, 5.4.0p2, 5.5.0a5
Could not test on Unity 5.2x and lower because there are no Virtual Reality Splash Image fields