Ensure that 2D meshes use a proper input mask #500

Job	Run time
📊 Static checks / Code style, file formatting, and docs	2m 25s
🍎 macOS / Editor (target=editor, tests=yes)	38m 8s
🍎 macOS / Template (target=template_release)	22m 4s
🐧 Linux / Editor w/ Mono (target=editor)	33m 15s
🐧 Linux / Editor with doubles and GCC sanitizers (target=editor, tests=yes, dev_build=yes, scu_build=yes, precision=double, use_asan=yes, use_ubsan=yes, linker=gold)	36m 36s
🍏 iOS / Template (target=template_release)	26m 45s
🤖 Android / Template (target=template_release)	27m 34s
🌐 Web / Template (target=template_release)	18m 18s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	29m 27s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	25m 58s
🐧 Linux / Template w/ Mono (target=template_release)	22m 14s
🏁 Windows / Editor (target=editor, tests=yes)	40m 12s
🐧 Linux / Minimal template (target=template_release, everything disabled)	14m 13s
🏁 Windows / Template (target=template_release)	28m 38s
🪲 Godot CPP / Build and test Godot CPP	6m 43s
	6h 12m 30s

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