Simpler return value from HashTable::add()/HashMap::add() and others

Simpler return value of HashTable::add/HashMap:add and others 

The current return value of HashTable::add() is a bool paired 
with an iterator object. The creation and destruction of that 
iterator object contributed to code size and since it was only 
used at a few places it was not worth it. 

Instead, let us return a bool paired with a pointer to the stored 
object. That is after all what the code using the iterator object 
wanted to have. I renamed the variable iterator -> storedValue 
which is 99% [magic number] of the patch. Most users of HashTable 
did not access iterator and did not have to change at all. 

This change saves roughly 100 KB binary size of an x64 content_shell 
built with clang. Other compilers, other architectures will save 
different amounts, most likely less since most are not 64 bit. 

The save is both in the instantiated ::add methods that don't have 
to create an iterator object, and in the callers that don't have 
to copy and destroy it. 

R=morrita@chromium.org 
RSR=eseidel@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=167217

[Daniel Bratell, 2014-02-14 16:47:07]

morrita, eseidel, can you please mark this again as lgtm and rslgtm because
https://codereview.chromium.org/138643003/ was broken (no base url) so CQ
couldn't handle it.

[Daniel Bratell, 2014-02-14 17:08:26]

The CQ bit was checked by bratell@opera.com

[Daniel Bratell, 2014-02-14 17:08:29]

The CQ bit was unchecked by bratell@opera.com

[eseidel, 2014-02-14 17:10:04]

lgtm

[commit-bot: I haz the power, 2014-02-14 17:10:33]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/bratell@opera.com/167123002/1

[commit-bot: I haz the power, 2014-02-14 19:19:10]

Change committed as 167217

[Daniel Bratell, 2014-02-18 08:12:06]

On 2014/02/14 19:19:10, I haz the power (commit-bot) wrote:
> Change committed as 167217

I tried to verify the change but unfortunately this ended up in a huge blink
roll of over a hundred changes.

That blink roll reduced binary size by 33 KB for Mac, 9 KB for Windows and 59 KB
in Linux. From that I can only say that it seems like the patch might have
worked and I won't spend any more time thinking about it.