AndroidLeakFixes$TEXT_LINE_POOL should not hold TextLine.sCached

Not sure why but Google's CI found that the code that's attempting to clear the sCached leak ends up on the shortest path for that leak, which makes no sense. The best way to avoid that is simply to not cache sCached but instance retrieve it each time, which isn't all that costly anyway.

┬───
│ GC Root: System class
│
├─ leakcanary.internal.InternalLeakCanary class
│    Leaking: NO (LeakCanaryApp↓ is not leaking and a class is never leaking)
│    ↓ static InternalLeakCanary._application
├─ androidx.fragment.app.LeakCanaryApp instance
│    Leaking: NO (Application is a singleton)
│    mBase instance of android.app.ContextImpl
│    ↓ Application.mActivityLifecycleCallbacks
│                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~
├─ java.util.ArrayList instance
│    Leaking: UNKNOWN
│    Retaining 440 B in 20 objects
│    ↓ ArrayList[2]
│               ~~~
├─ leakcanary.AndroidLeakFixes$Companion$onActivityDestroyed$1 instance
│    Leaking: UNKNOWN
│    Retaining 44 B in 3 objects
│    Anonymous class implementing android.app.Application$ActivityLifecycleCallbacks
│    ↓ AndroidLeakFixes$Companion$onActivityDestroyed$1.$block
│                                                       ~~~~~~
├─ leakcanary.AndroidLeakFixes$TEXT_LINE_POOL$apply$1$3 instance
│    Leaking: UNKNOWN
│    Retaining 16 B in 1 objects
│    Anonymous subclass of kotlin.jvm.internal.Lambda
│    ↓ AndroidLeakFixes$TEXT_LINE_POOL$apply$1$3.$sCached
│                                                ~~~~~~~~
├─ android.text.TextLine[] array
│    Leaking: UNKNOWN
│    Retaining 36.6 kB in 587 objects
│    ↓ TextLine[1]
│              ~~~

I'm not sure if having additional reports of this helps, but I believe we are seeing the same, in our leak detecting instrumentation tests.

┬───
│ GC Root: System class
│
├─ com.squareup.picasso.PicassoProvider class
│    Leaking: NO (CashRegisterTestApplication↓ is not leaking and a class is never leaking)
│    ↓ static PicassoProvider.context
├─ com.izettle.android.cashregister.CashRegisterTestApplication instance
│    Leaking: NO (Application is a singleton)
│    mBase instance of android.app.ContextImpl
│    ↓ Application.mActivityLifecycleCallbacks
│                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~
├─ java.util.ArrayList instance
│    Leaking: UNKNOWN
│    Retaining 464 B in 25 objects
│    ↓ ArrayList[4]
│               ~~~
├─ leakcanary.AndroidLeakFixes$Companion$onActivityDestroyed$1 instance
│    Leaking: UNKNOWN
│    Retaining 44 B in 3 objects
│    Anonymous class implementing android.app.Application$ActivityLifecycleCallbacks
│    ↓ AndroidLeakFixes$Companion$onActivityDestroyed$1.$block
│                                                       ~~~~~~
├─ leakcanary.AndroidLeakFixes$TEXT_LINE_POOL$apply$1$3 instance
│    Leaking: UNKNOWN
│    Retaining 16 B in 1 objects
│    Anonymous subclass of kotlin.jvm.internal.Lambda
│    ↓ AndroidLeakFixes$TEXT_LINE_POOL$apply$1$3.$sCached
│                                                ~~~~~~~~
├─ android.text.TextLine[] array
│    Leaking: UNKNOWN
│    Retaining 334.1 kB in 5478 objects
│    ↓ TextLine[0]
│              ~~~

METADATA

Please include this in bug reports and Stack Overflow questions.

Build.VERSION.SDK_INT: 21
Build.MANUFACTURER: unknown
LeakCanary version: 2.10
App process name: com.izettle.android.cashregister.test
Class count: 8676
Instance count: 372955
Primitive array count: 102783
Object array count: 51825
Thread count: 30
Heap total bytes: 38598380
Bitmap count: 416
Bitmap total bytes: 0
Large bitmap count: 0
Large bitmap total bytes: 0
Db 1: open /data/data/com.izettle.android.cashregister.test/databases/androidx.work.workdb
Stats: LruCache[maxSize=3000,hits=106555,misses=254810,hitRate=29%] RandomAccess[bytes=17822749,reads=254810,travel=340112493765,range=44325073,size=46561021]
assertionTag: BeforeActivitiesDestroyed
waitForRetainedDurationMillis: 5133
totalDurationMillis: 23506
Analysis duration: 14828 ms
Heap dump file path: /data/data/com.izettle.android.cashregister.test/files/instrumentation_tests_2023-02-20_08-05-06_878.hprof
Heap dump timestamp: 1676909125245
Heap dump duration: 656 ms

square / leakcanary

AndroidLeakFixes$TEXT_LINE_POOL should not hold TextLine.sCached #2471