GN: Fix some breakage for os==chromeos build

build/config/linux/BUILD.gn:
* Usage of generate_library_loader for libbrlapi was incorrect; there
* was nothing provided for "functions". This is now an empty list.

chrome/chrome_common.gypi
chrome/common/BUILD.gn
* Reference to a removed file, chrome_version_info_linux.cc

chromeos/BUILD.gn
components/pairing/BUILD.gn
* Usage of removed proto_{in,out}_dir in proto_library rules.

content/gpu/BUILD.gn
* Typo in reference to third_party/libva:libva_config

ui/views/BUILD.gn
* Attempt to filter source files out of
* gypi_values.views_unittests_sources by subdirectory path. Fortunately
* that variable already doesn't include the files that were supposed
* to be filtered out, so the rule is simply removed.

BUG=388412
TEST=Create a target that builds //mojo/public, build with os==chromeos

R=brettw@chromium.org

Review URL: https://codereview.chromium.org/550423002

Cr-Original-Commit-Position: refs/heads/master@{#293964}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 418e04caaf5701fac99ae766ab60f2e65279fccd

config/linux/BUILD.gn

@@ -142,6 +142,20 @@ if (use_brlapi) {
     output_cc = "libbrlapi_loader.cc"
     header = "<brlapi.h>"
     config = ":brlapi_config"
+
+    functions = [
+      "brlapi_getHandleSize",
+      "brlapi_error_location",
+      "brlapi_strerror",
+      "brlapi__acceptKeys",
+      "brlapi__openConnection",
+      "brlapi__closeConnection",
+      "brlapi__getDisplaySize",
+      "brlapi__enterTtyModeWithPath",
+      "brlapi__leaveTtyMode",
+      "brlapi__writeDots",
+      "brlapi__readKey",
+    ]
   }
 }