[zircon][utest][pager] Reland "Exclude root-resource tests at runtime, not compile"

This is a reland of fd4a750800aeabfe01beb0062a1eee7c873c3608

Original change's description:
> [zircon][utest][pager] Exclude root-resource tests at runtime, not compile
>
> Rather than using #ifdef BUILD_COMBINED_TESTS to decide whether the
> root resource handle will be available for tests that need it, instead
> use a weak symbol for get_root_resource and check it at runtime.
> This obviates the need to compile the test sourcce file differently for
> the integrated and standalone cases.
>
> Bug: BLD-325
> Test: CQ
> Change-Id: I48e3f192af87da354f05cd9b75c6e1124d4e2106

Bug: BLD-325
Change-Id: I05613f4756a5f573e681e540c09da07f02d25e98
3 files changed
tree: aae59645ed07337766a957b13263e6b713713794
  1. .cargo/
  2. boards/
  3. build/
  4. buildtools/
  5. bundles/
  6. docs/
  7. garnet/
  8. peridot/
  9. products/
  10. scripts/
  11. sdk/
  12. src/
  13. zircon/
  14. .clang-format
  15. .dir-locals.el
  16. .gitattributes
  17. .gitignore
  18. .gn
  19. AUTHORS
  20. CODE_OF_CONDUCT.md
  21. CONTRIBUTING.md
  22. LICENSE
  23. OWNERS
  24. PATENTS
  25. README.md
  26. rustfmt.toml
README.md

Fuchsia

Pink + Purple == Fuchsia (a new operating system)

What is Fuchsia?

Fuchsia is a modular, capability-based operating system. Fuchsia runs on modern 64-bit Intel and ARM processors.

Fuchsia is an open source project with a code of conduct that we expect everyone who interacts with the project to respect.

How can I build and run Fuchsia?

See Getting Started.

Where can I learn more about Fuchsia?

See the documentation.