On Android, the core problem is here, where we always pretend the cursor is unset (default to the end of the text).
        start(profile, url, text, -1, preventInlineAutocomplete, focusedFromFakebox);
https://cs.chromium.org/chromium/src/chrome/android/java/src/org/chromium/chrome/browser/omnibox/AutocompleteController.java?l=101

Claiming!

Thank you!

jdonnelly, mark asks: "Can one of you in LAX with an iOS device check to see if iOS uses cursor position already?  See repro steps on  crbug.com/738559 "

Confirmed: iOS behavior matches Android, not desktop. The cursor-aware "new york times" suggestions do not appear when following the repro steps.

Thanks for checking on iOS.  When looking for the code that needs to be added to make iOS work, I found a relevant bug ( bug 726702 ):

// TODO( crbug.com/726702 ): Implement this and have |SetWindowTextAndCaretPos()|
// call it.
void OmniboxViewIOS::SetCaretPos(size_t caret_pos) {}
https://cs.chromium.org/chromium/src/ios/chrome/browser/ui/omnibox/omnibox_view_ios.mm?l=237-239

I'd also want to make sure that SetWindowTextAndCaretPos is called at the right places.  I *think* it is because cursor position works on Mac, and Mac only calls SetWindowTextAndCaretPos in one place (OnTemporaryTextMaybeChanged()), and it's also called in the same place in iOS.

I *think* implementing that function should be easy someone with an iOS build setup.  The Mac code for SetCaretPos() is only two lines long; I can't imagine iOS being that different...
https://cs.chromium.org/chromium/src/chrome/browser/ui/cocoa/omnibox/omnibox_view_mac.mm?l=335-338

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2985e918abe76fc27e19bee76dbadd3126c0a488

commit 2985e918abe76fc27e19bee76dbadd3126c0a488
Author: Mark Pearson <mpearson@chromium.org>
Date: Mon Sep 25 22:17:36 2017

Omnibox - Use Cursor Position When Generating Suggestions on Android

Both the local suggestion providers and the server can provide better
suggestions with this context.

Remove a now redundant / unnecessary function here.

Bug:  738559 
Change-Id: I4780c99a1347b2aa80bc52cb57a1f772709b3ad8
Reviewed-on: https://chromium-review.googlesource.com/665514
Commit-Queue: Mark Pearson <mpearson@chromium.org>
Reviewed-by: Ted Choc <tedchoc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#504184}
[modify] https://crrev.com/2985e918abe76fc27e19bee76dbadd3126c0a488/chrome/android/java/src/org/chromium/chrome/browser/omnibox/AutocompleteController.java
[modify] https://crrev.com/2985e918abe76fc27e19bee76dbadd3126c0a488/chrome/android/java/src/org/chromium/chrome/browser/omnibox/LocationBarLayout.java
[modify] https://crrev.com/2985e918abe76fc27e19bee76dbadd3126c0a488/chrome/android/javatests/src/org/chromium/chrome/browser/omnibox/UrlBarTest.java
[modify] https://crrev.com/2985e918abe76fc27e19bee76dbadd3126c0a488/chrome/test/android/javatests/src/org/chromium/chrome/test/util/OmniboxTestUtils.java

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b89f46d5db2f3ba8ae3d40200f7b79046385e8eb

commit b89f46d5db2f3ba8ae3d40200f7b79046385e8eb
Author: Justin Donnelly <jdonnelly@google.com>
Date: Wed Oct 25 18:27:02 2017

Implement OmniboxViewIOS::GetSelectionBounds.

This will supply the correct cursor position to the suggest backend,
allowing us to enable cursor-position-sensitive suggestions.

Bug:  738559 
Change-Id: I6a9e72f747dc50fb000ddacb0f77503fdd4b6fb3
Reviewed-on: https://chromium-review.googlesource.com/728720
Reviewed-by: Rohit Rao (ping after 24h) <rohitrao@chromium.org>
Commit-Queue: Justin Donnelly <jdonnelly@chromium.org>
Cr-Commit-Position: refs/heads/master@{#511524}
[modify] https://crrev.com/b89f46d5db2f3ba8ae3d40200f7b79046385e8eb/ios/chrome/browser/ui/omnibox/omnibox_view_ios.mm

It seems like the CL in comment 12 fixed the bug? 

This still needs to be enabled on the server.  And right now the experiments look confusing, so it's possible something isn't working right.  Leaving open until it's fully launched.

This has been launched on Android.

iOS still need verification before launch.

iOS has been verified and launched.  Marking as fixed. :-) (at last!)