avoid !! operator

Avoid using the not-null assertion operator (!!) as it can cause runtime crashes if the assumption about non-nullability is incorrect. Instead, use safer alternatives that provide better error handling and code clarity.

Preferred alternatives:

1. Use checkNotNull() or requireNotNull() for explicit null validation with meaningful error messages: ```kotlin // Instead of: drawable = draweeHolder.topLevelDrawable!!

// Use: drawable = checkNotNull(draweeHolder.topLevelDrawable) { “Drawable should not be null” }

2. **Use Elvis operator (`?:`)** for providing fallback values or throwing exceptions:
```kotlin
// Instead of:
val local = instance().connectNative(pageId, remote)
local ?: throw IllegalStateException("Can't open failed connection")

// Use:
instance().connectNative(pageId, remote) ?: throw IllegalStateException("Can't open failed connection")

1. Use smart casting with is checks to avoid unnecessary null states: ```kotlin // Instead of: if (value !is Boolean) { throw ClassCastException(“Dynamic value from Object is not a boolean”) } return value as Boolean

// Use: if (value is Boolean) { return value } throw ClassCastException(“Dynamic value from Object is not a boolean”) ```

The !! operator should only be used when you have absolute certainty that the value cannot be null, and even then, consider if a more explicit null check would make the code clearer and safer for future maintainers.