Summary:
Special thanks for Joshua Gross for flagging this problem!
This diff implements a custom evicting hash map designed specially to hold text measurement information. The key feature of this is custom equality checks and hashing functions.
They are designed around the following principals:
* Decorative text attributes (such as color, shadows, etc) has no effect on layout, therefore they should not be taking into account;
* `minimum height`, `minimum width`, and `maximum height` don't affect the measurement;
* the value of `layout metrics` are important only for `attachment` fragments.
After I redo all tests, I will enable this for Android-specific TextLayoutManager in separate diff.
Changelog: [Internal] Fabric-specific internal change.
Reviewed By: sammy-SC
Differential Revision: D18848583
fbshipit-source-id: 46c2fc445fbd1823afc5e7498e37de75381258b1
Valentin Shergin