test::scale

Timing helpers for the scale tests of the tree.

Detailed description

Test builds are debug builds at -O0, so a time in milliseconds measures the build, not the code (scene-tree-model-view §TMQ-4). A scale test runs each gesture at two sizes and asserts a ratio. The helpers moved here from testSceneTreeGestures when testConfigScale became their second user (test-system-revamp §TSR-S-7, config-ui §CFGT-4).