[Autofill/Autocomplete Feature] Substring matching instead of prefix matching (Blink).

[Autofill/Autocomplete Feature] Substring matching instead of prefix matching (Blink).

With present implementation autofill/autocomplete suggestions are matched for
prefix for what user has typed.

This patch brings in suggestions with substring matching (i.e. substring matching
to the beginning of suggestion tokens) instead of prefix matching.

Patch spread across chromium side as well as on Blink side.
[1] Blink side: https://codereview.chromium.org/1208063002/ (This CL)
    - aims to cache the suggestion start index with |WebFormControlElement| so that
      chromium content can make use of it on setting selection range.
[2] Chromium side: https://codereview.chromium.org/1208133002/
    - aims to add IPC changes to introduce |match_start| for suggestion preview in
      case of password manager and autocomplete so that additional calulation on
      renderer to get selection range in not needed.
[3] Chromium side: https://codereview.chromium.org/962673004/ 
    - Substring match instead of prefixes.

BUG=77194

[Pritam Nikam, 2015-06-25 16:18:01]

pritam.nikam@samsung.com changed reviewers:
+ rouslan@chromium.org

[Pritam Nikam, 2015-06-25 16:19:00]

Hi Rouslan,
IMO, I don't think we need this patch, please let me know if I'm missing any
case here.

Thanks!

[please use gerrit instead, 2015-06-25 17:24:45]

On 2015/06/25 16:19:00, Pritam Nikam wrote:
> Hi Rouslan,
> IMO, I don't think we need this patch, please let me know if I'm missing any
> case here.
> 
> Thanks!


Why do you say that we don't need this patch?

[Pritam Nikam, 2015-06-25 18:00:20]

On 2015/06/25 17:24:45, Rouslan wrote:
> On 2015/06/25 16:19:00, Pritam Nikam wrote:
> > Hi Rouslan,
> > IMO, I don't think we need this patch, please let me know if I'm missing any
> > case here.
> > 
> > Thanks!
> 
> 
> Why do you say that we don't need this patch?


Thanks Rouslan for quick reply!

IMO, blink side changes not required. Reason being, we'll get the calculated
|match_start| offset within suggestion string over the wire, that we can simply
use to set this to selection range as is. Something like below:

node->setSelectionRange(std::min(match_start, node->maxLength()),
                        node->suggestedValue().length());

Moreover, I didn't find any async |AutofillAgent::PreviewFieldWithValue| call as
well.
I've added just IPC related changes just to get some idea on how it may look
(https://codereview.chromium.org/1208133002/).

Please let me know if I'm missing any thing here.

Thanks!

[please use gerrit instead, 2015-06-25 18:33:15]

On 2015/06/25 18:00:20, Pritam Nikam wrote:
> On 2015/06/25 17:24:45, Rouslan wrote:
> > On 2015/06/25 16:19:00, Pritam Nikam wrote:
> > > Hi Rouslan,
> > > IMO, I don't think we need this patch, please let me know if I'm missing
any
> > > case here.
> > > 
> > > Thanks!
> > 
> > 
> > Why do you say that we don't need this patch?
> 
> 
> Thanks Rouslan for quick reply!
> 
> IMO, blink side changes not required. Reason being, we'll get the calculated
> |match_start| offset within suggestion string over the wire, that we can
simply
> use to set this to selection range as is. Something like below:
> 
> node->setSelectionRange(std::min(match_start, node->maxLength()),
>                         node->suggestedValue().length());
> 
> Moreover, I didn't find any async |AutofillAgent::PreviewFieldWithValue| call
as
> well.
> I've added just IPC related changes just to get some idea on how it may look
> (https://codereview.chromium.org/1208133002/).
> 
> Please let me know if I'm missing any thing here.
> 
> Thanks!

Oh I see. I was expecting that line to look like this:

node->setSelectionRange(std::min(node->suggestedValueStart(),
node->maxLength()),
                        node->suggestedValue().length());

Let me take a look at your IPC patch to understand your point better...

[Pritam Nikam, 2015-06-26 14:04:43]

On 2015/06/25 18:33:15, Rouslan wrote:
> On 2015/06/25 18:00:20, Pritam Nikam wrote:
> > On 2015/06/25 17:24:45, Rouslan wrote:
> > > On 2015/06/25 16:19:00, Pritam Nikam wrote:
> > > > Hi Rouslan,
> > > > IMO, I don't think we need this patch, please let me know if I'm missing
> any
> > > > case here.
> > > > 
> > > > Thanks!
> > > 
> > > 
> > > Why do you say that we don't need this patch?
> > 
> > 
> > Thanks Rouslan for quick reply!
> > 
> > IMO, blink side changes not required. Reason being, we'll get the calculated
> > |match_start| offset within suggestion string over the wire, that we can
> simply
> > use to set this to selection range as is. Something like below:
> > 
> > node->setSelectionRange(std::min(match_start, node->maxLength()),
> >                         node->suggestedValue().length());
> > 
> > Moreover, I didn't find any async |AutofillAgent::PreviewFieldWithValue|
call
> as
> > well.
> > I've added just IPC related changes just to get some idea on how it may look
> > (https://codereview.chromium.org/1208133002/).
> > 
> > Please let me know if I'm missing any thing here.
> > 
> > Thanks!
> 
> Oh I see. I was expecting that line to look like this:
> 
> node->setSelectionRange(std::min(node->suggestedValueStart(),
> node->maxLength()),
>                         node->suggestedValue().length());
> 
> Let me take a look at your IPC patch to understand your point better...

Please have a look at [1] and [2] for password form and autocomplete field
suggestions (rest can be overlooked).

[1].
https://codereview.chromium.org/1208133002/diff/20001/components/autofill/con...
[2].
https://codereview.chromium.org/1208133002/diff/20001/components/autofill/con...

[please use gerrit instead, 2015-06-28 00:43:51]

You're right, this change is not necessary. Let's discard it.