Remove data classes from public FC API

[tillh-stripe]

Summary

Motivation

Testing

• Added tests
• Modified tests
• Manually verified

Screenshots

Before	After
before screenshot	after screenshot

Changelog

[github-actions]

Diffuse output:

OLD: paymentsheet-example-release-master.apk (signature: V1, V2)
NEW: paymentsheet-example-release-pr.apk (signature: V1, V2)

          │          compressed           │         uncompressed          
          ├───────────┬───────────┬───────┼───────────┬───────────┬───────
 APK      │ old       │ new       │ diff  │ old       │ new       │ diff  
──────────┼───────────┼───────────┼───────┼───────────┼───────────┼───────
      dex │   3.9 MiB │   3.9 MiB │ -20 B │   8.6 MiB │   8.6 MiB │ +24 B 
     arsc │   2.3 MiB │   2.3 MiB │   0 B │   2.3 MiB │   2.3 MiB │   0 B 
 manifest │   5.1 KiB │   5.1 KiB │   0 B │  25.6 KiB │  25.6 KiB │   0 B 
      res │ 933.6 KiB │ 933.6 KiB │   0 B │   1.5 MiB │   1.5 MiB │   0 B 
   native │   2.6 MiB │   2.6 MiB │   0 B │     6 MiB │     6 MiB │   0 B 
    asset │   2.9 MiB │   2.9 MiB │  -1 B │   2.9 MiB │   2.9 MiB │  -1 B 
    other │   196 KiB │   196 KiB │  +4 B │ 430.6 KiB │ 430.6 KiB │   0 B 
──────────┼───────────┼───────────┼───────┼───────────┼───────────┼───────
    total │  12.8 MiB │  12.8 MiB │ -17 B │  21.7 MiB │  21.7 MiB │ +23 B 

 DEX     │ old   │ new   │ diff      
─────────┼───────┼───────┼───────────
   files │     1 │     1 │ 0         
 strings │ 42651 │ 42651 │ 0 (+1 -1) 
   types │ 14147 │ 14147 │ 0 (+0 -0) 
 classes │ 11774 │ 11774 │ 0 (+0 -0) 
 methods │ 60439 │ 60439 │ 0 (+0 -0) 
  fields │ 40070 │ 40070 │ 0 (+0 -0) 

 ARSC    │ old  │ new  │ diff 
─────────┼──────┼──────┼──────
 configs │  242 │  242 │  0   
 entries │ 6252 │ 6252 │  0

APK

    compressed    │   uncompressed    │                                
──────────┬───────┼───────────┬───────┤                                
 size     │ diff  │ size      │ diff  │ path                           
──────────┼───────┼───────────┼───────┼────────────────────────────────
  3.9 MiB │ -20 B │   8.6 MiB │ +24 B │ ∆ classes.dex                  
 53.4 KiB │  +5 B │ 118.3 KiB │   0 B │ ∆ META-INF/CERT.SF             
 50.1 KiB │  -2 B │ 118.2 KiB │   0 B │ ∆ META-INF/MANIFEST.MF         
    984 B │  -1 B │     852 B │  -1 B │ ∆ assets/dexopt/baseline.profm 
  1.2 KiB │  +1 B │   1.2 KiB │   0 B │ ∆ META-INF/CERT.RSA            
──────────┼───────┼───────────┼───────┼────────────────────────────────
    4 MiB │ -17 B │   8.8 MiB │ +23 B │ (total)

DEX

STRINGS:

   old   │ new   │ diff      
  ───────┼───────┼───────────
   42651 │ 42651 │ 0 (+1 -1) 
  
  + ~~R8{"backend":"dex","compilation-mode":"release","has-checksums":false,"min-api":21,"pg-map-id":"35b7e2f","r8-mode":"full","version":"8.5.35"}
  
  - ~~R8{"backend":"dex","compilation-mode":"release","has-checksums":false,"min-api":21,"pg-map-id":"829c6e8","r8-mode":"full","version":"8.5.35"}