Fix internal KDocs in ViewportHint

Fixing KDocs that were accidentally copied between multiple fields

Test: N/A docs change only
Change-Id: I3d01eb839b3c4a974b3974b9819efd1efbc2d08b

diff --git a/paging/common/src/main/kotlin/androidx/paging/ViewportHint.kt b/paging/common/src/main/kotlin/androidx/paging/ViewportHint.kt
index 3b183cf..e11089d 100644
--- a/paging/common/src/main/kotlin/androidx/paging/ViewportHint.kt
+++ b/paging/common/src/main/kotlin/androidx/paging/ViewportHint.kt

@@ -16,6 +16,8 @@
 
 package androidx.paging
 
+import androidx.paging.PagingSource.LoadResult.Page
+
 /**
  * Load access information blob, containing information from presenter.
  */
@@ -23,11 +25,13 @@
     /** Page index offset from initial load */
     val pageOffset: Int,
     /**
-     * Distance from hint to first loaded item: `anchorPosition - firstLoadedItemPosition`
+     * Original index of item in the [Page] with [pageOffset].
      *
-     * Zero indicates access at boundary
-     * Positive -> Within loaded range or in placeholders if greater than size of last page.
-     * Negative -> placeholder access.
+     * Three cases to consider:
+     *  - [indexInPage] in Page.data.indices -> Hint references original item directly
+     *  - [indexInPage] > Page.data.indices -> Hint references a placeholder after the last
+     *    presented item.
+     *  - [indexInPage] < 0 -> Hint references a placeholder before the first presented item.
      */
     val indexInPage: Int,
     /**
@@ -39,7 +43,7 @@
      */
     val presentedItemsBefore: Int,
     /**
-     * Distance from hint to first presented item: `anchorPosition - firstLoadedItemPosition`
+     * Distance from hint to last presented item: `size - index - placeholdersAfter - 1`
      *
      * Zero indicates access at boundary
      * Positive -> Within loaded range or in placeholders if greater than size of last page.