Native: remove harmful assertions from NaiveSourceBasedFileEntryImpl

These assertions checked that nobody requests line and column number
for the UNDEFINED_OFFSET.
But diagnostic and crash reporting tools might request line and column,
and crashing during crash reporting is not great.

So handle UNDEFINED_OFFSET gracefully instead, in a conventional manner.

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/AdditionalIrUtils.kt

@@ -206,14 +206,14 @@ class NaiveSourceBasedFileEntryImpl(
     }
 
     override fun getLineNumber(offset: Int): Int {
-        assert(offset != UNDEFINED_OFFSET)
         if (offset == SYNTHETIC_OFFSET) return 0
+        if (offset < 0) return -1
         return calculatedBeforeLineNumbers.get(offset)
     }
 
     override fun getColumnNumber(offset: Int): Int {
-        assert(offset != UNDEFINED_OFFSET)
         if (offset == SYNTHETIC_OFFSET) return 0
+        if (offset < 0) return -1
         val lineNumber = getLineNumber(offset)
         return offset - lineStartOffsets[lineNumber]
     }