Conversion of AbstractInternalSource and related Java files in AOSP QuickSearchBox App to Kotlin

Converted several related Java files in QuickSearchBox to Kotlin. Java files were added to exclude_srcs in Android.bp and target was built successfully against Kotlin 1.7.

Bug: 239665416

Test: manual testing with bramble device, unit tests ran with atest QuickSearchBoxTests with result:
Summary (Test executed with 1 devices.)
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arm64-v8a QuickSearchBoxTests: Passed: 50, Failed: 0, Ignored: 0, Assumption Failed: 0,

All tests passed!

Change-Id: If51906d977e3d6bd25ffbe86e58f11d866e86389