Cleanup: Merge BlGridLayoutImpl into BlGridLayout

[tinchodias]

BlGridLayoutImpl is only referenced from BlGridLayout's initialize, and then it's used by forwarding BlGridLayout's API to BlGridLayoutImpl.

This may be a reminiscence of a port from another library, as the Impl suffix is not common in Pharo.

[tinchodias]

Out of curiosity, I looked for the history.
When you check for history of BlGridLayout methods in Calypso, you jump until the migration from Filetree to Tonel. I checked in an external tool for history before that commit, and the layouts were already in the beginning of this repo: 49d20c1 (~2016).

The original sources should be smalltalkhub. I looked in their archives and there are 2 candidates:

• http://smalltalkhub.com/GlennCavarle/BlocOld-20160807
• http://smalltalkhub.com/AlainPlantec/Bloc

Maybe @plantec knows

[tinchodias]

Same happens between BlFlowLayoutMeasurer and BlFlowLayout.

[plantec]

ahh, ok. I think Glenn did it.
A port from a java API I guess

[tinchodias]

This comment in linear layout lead me to Android (https://developer.android.com/reference/android/view/View.MeasureSpec)

Bloc/src/Bloc-Layout/BlLinearLayoutMeasurer.class.st

Lines 262 to 265 in a5fe2d3

	"The lengthMode is either UNSPECIFIED or AT_MOST, and
	this child is only laid out using excess space.
	Measure using FIT_CONTENT so that we can find out the view's optimal length.
	We'll restore the original length of 0 after measurement."

[tinchodias]

Additional info (weird): Both BlGridLayoutImpl and BlGridLayout are subclasses of BlLayout