Speed up rendering of the input method candidate window.

Speed up rendering of the input method candidate window.

UpdateCandidates() was not efficient as it was always updating candidates.
We don't have to update candidates if the user is just moving the cursor
in the same page in the candidate window.

BUG=chromium-os:6509
TEST=confirmed that the candidate window worked as before and rendering is faster by the following steps:
1. start a youtube video to add loads
2. start typing with mozc
3. type a
4. hold the space key for a while.

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=67956

[satorux1, 2010-12-01 09:25:31]

http://codereview.chromium.org/5444001/diff/1/chrome/browser/chromeos/input_m...
File chrome/browser/chromeos/input_method/candidate_window.cc (right):

http://codereview.chromium.org/5444001/diff/1/chrome/browser/chromeos/input_m...
chrome/browser/chromeos/input_method/candidate_window.cc:873: }
Hmm, rietveld didn't do a good job for showing diffs here. The contents in "if
(should_update)" block is almost identical to the original code.

[Yusuke Sato, 2010-12-01 22:39:02]

http://codereview.chromium.org/5444001/diff/9001/chrome/browser/chromeos/inpu...
File chrome/browser/chromeos/input_method/candidate_window.cc (right):

http://codereview.chromium.org/5444001/diff/9001/chrome/browser/chromeos/inpu...
chrome/browser/chromeos/input_method/candidate_window.cc:813: const
InputMethodLookupTable& lookup_table) {
Using lookup_table_ and lookup_table at the same time looks a bit confusing to
me. How about renaming the parameter to new_lookup_table or something similar?

[Yusuke Sato, 2010-12-01 22:39:17]

forgot to write:
LGTM

On 2010/12/01 22:39:02, Yusuke Sato wrote:
>
http://codereview.chromium.org/5444001/diff/9001/chrome/browser/chromeos/inpu...
> File chrome/browser/chromeos/input_method/candidate_window.cc (right):
> 
>
http://codereview.chromium.org/5444001/diff/9001/chrome/browser/chromeos/inpu...
> chrome/browser/chromeos/input_method/candidate_window.cc:813: const
> InputMethodLookupTable& lookup_table) {
> Using lookup_table_ and lookup_table at the same time looks a bit confusing to
> me. How about renaming the parameter to new_lookup_table or something similar?

[satorux1, 2010-12-02 02:13:07]

http://codereview.chromium.org/5444001/diff/9001/chrome/browser/chromeos/inpu...
File chrome/browser/chromeos/input_method/candidate_window.cc (right):

http://codereview.chromium.org/5444001/diff/9001/chrome/browser/chromeos/inpu...
chrome/browser/chromeos/input_method/candidate_window.cc:813: const
InputMethodLookupTable& lookup_table) {
On 2010/12/01 22:39:04, Yusuke Sato wrote:
> Using lookup_table_ and lookup_table at the same time looks a bit confusing to
> me. How about renaming the parameter to new_lookup_table or something similar?

Agreed. Done.