Have SkTArray explicitly call default constructors.

Have SkTArray state that it default-initializes.

The current comments in SkTArray lead one to believe that it is default
constructing all types. However, it is not calling the default
constructor for primitive types, it is actually default-initializing.

R=bsalomon@google.com

Committed: https://code.google.com/p/skia/source/detail?r=13909

[bsalomon, 2014-03-24 13:16:57]

Is this something you need? I'm not necessarily opposed but if we don't need
this behavior I'd be OK with just updating the comments to reflect the current
implementation. I imagine that all the current users of TArray with primitive
types are OK with the current behavior.

[bungeman-skia, 2014-03-24 13:56:56]

On 2014/03/24 13:16:57, bsalomon wrote:
> Is this something you need? I'm not necessarily opposed but if we don't need
> this behavior I'd be OK with just updating the comments to reflect the current
> implementation. I imagine that all the current users of TArray with primitive
> types are OK with the current behavior.

I'll have to take a look at who may be using it with primitives. Obviously, one
would prefer such cases to use SkTDArray if that's the behavior which is
desired. I was just very surprised while writing the TArrayTest.cpp (prior to
last week we had no tests specifically for this class at all).

[bungeman-skia, 2014-03-24 15:45:48]

New patch, just change the comments so that they reflect what the code actually
does.

https://codereview.chromium.org/208393006/diff/20001/include/core/SkTArray.h
File include/core/SkTArray.h (right):

https://codereview.chromium.org/208393006/diff/20001/include/core/SkTArray.h#...
include/core/SkTArray.h:260: * Pushes or pops from the back to resize. Pushes
will be default
Interestingly, this comment is actually already correct.

[bsalomon, 2014-03-24 15:49:57]

lgtm

[bungeman-skia, 2014-03-24 15:55:06]

Committed patchset #2 manually as r13909 (presubmit successful).