Several fixes to recovery map math.

* Fix incorrect conversion conversion from RGB to YUV using bt.2100 when
  the data is actually assumed to be srgb (although this will get
  improved further soon) in map application.
* Fix incorrectly calculating luminance directly from luma in map
  generation; we need to convert from YUV to RGB first. This also
  involved updating the sampling functions to sample entire pixels.
* Some cleanup to structure of recoverymapmath files.
* Call all public lib functions in recovermap_test to force linking, and
  therefore verify that the lib actually builds properly.

Test: builds (including the test, which verifies linking now)
Bug: 252835416
No-Typo-Check: incorrectly interpretting code as a comment
Change-Id: I13565145dc6efcdf642981a1e52420d662152737
diff --git a/libs/jpegrecoverymap/tests/Android.bp b/libs/jpegrecoverymap/tests/Android.bp
index 41af991..8f37954 100644
--- a/libs/jpegrecoverymap/tests/Android.bp
+++ b/libs/jpegrecoverymap/tests/Android.bp
@@ -27,7 +27,15 @@
     srcs: [
         "recoverymap_test.cpp",
     ],
+    shared_libs: [
+        "libimage_io",
+        "libjpeg",
+        "liblog",
+    ],
     static_libs: [
+        "libgtest",
+        "libjpegdecoder",
+        "libjpegencoder",
         "libjpegrecoverymap",
     ],
 }