Remove cmake visibility flags.

This Cl removes the visiblity flags from the CMake file. In both
Debug and Release mode on OSX setting these flags caused piles
of warnings about mis-matched visibility settings throughout the
third_party libraries.

This CL fixes that by removing the flags. This maynot be the right
way to fix this, but it does fix the warnings. We need to decide
if we want to hide symbols by default and, if so, figure out how
to fix the downstream projects.

Change-Id: I8ee7422cfa2aec3715dba226da58e974f39e0d18
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/100420
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Commit-Queue: Dan Sinclair <dsinclair@chromium.org>

CMakeLists.txt

@@ -313,7 +313,6 @@ function(common_compile_options TARGET)
     target_compile_options(${TARGET} PRIVATE
       -fno-exceptions
       -fno-rtti
-      -fvisibility-inlines-hidden
     )
 
     if (${DAWN_ENABLE_MSAN})

src/tint/CMakeLists.txt

@@ -648,9 +648,6 @@ target_link_libraries(tint_val tint_utils_io)
 add_library(libtint ${TINT_LIB_SRCS})
 tint_default_compile_options(libtint)
 target_link_libraries(libtint tint_diagnostic_utils)
-if (${COMPILER_IS_LIKE_GNU})
-  target_compile_options(libtint PRIVATE -fvisibility=hidden)
-endif()
 if (${TINT_SYMBOL_STORE_DEBUG_NAME})
     target_compile_definitions(libtint PUBLIC "TINT_SYMBOL_STORE_DEBUG_NAME=1")
 endif()