CMake: normalize FOLDER property for third_party targets

Rather than set the FOLDER property from within certain third-party
CMakeLists.txt, do so from the root, and make them all go to a
"third_party" folder.

Bug: b/145758253
Change-Id: I7b9f69a8f16be8ef6e0d153fc28ac4f6c3d64e5e
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/48368
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Antonio Maiorano <amaiorano@google.com>
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8c68435..a966fc6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -577,12 +577,15 @@
 # LLVM
 ###########################################################
 add_subdirectory(${THIRD_PARTY_DIR}/llvm-${SWIFTSHADER_LLVM_VERSION} EXCLUDE_FROM_ALL)
+set_target_properties(llvm PROPERTIES FOLDER "third_party")
 
 ###########################################################
 # Subzero
 ###########################################################
 add_subdirectory(${THIRD_PARTY_DIR}/llvm-subzero EXCLUDE_FROM_ALL)
 add_subdirectory(${THIRD_PARTY_DIR}/subzero EXCLUDE_FROM_ALL)
+set_target_properties(llvm-subzero PROPERTIES FOLDER "third_party")
+set_target_properties(subzero PROPERTIES FOLDER "third_party")
 
 ###########################################################
 # marl
@@ -590,6 +593,7 @@
 if(BUILD_MARL)
     set(MARL_THIRD_PARTY_DIR ${THIRD_PARTY_DIR})
     add_subdirectory(${THIRD_PARTY_DIR}/marl)
+    set_target_properties(marl PROPERTIES FOLDER "third_party")
 endif()
 
 if(MARL_THREAD_SAFETY_ANALYSIS_SUPPORTED)
@@ -609,6 +613,7 @@
 ###########################################################
 if(SWIFTSHADER_ENABLE_ASTC)
     add_subdirectory(${THIRD_PARTY_DIR}/astc-encoder)
+    set_target_properties(astc-encoder PROPERTIES FOLDER "third_party")
 endif()
 
 ###########################################################
@@ -621,6 +626,10 @@
     # gtest finds python, which picks python 2 first, if present.
     # We need to undo this so that SPIR-V can later find python3.
     unset(PYTHON_EXECUTABLE CACHE)
+    set_target_properties(gmock PROPERTIES FOLDER "third_party")
+    set_target_properties(gmock_main PROPERTIES FOLDER "third_party")
+    set_target_properties(gtest PROPERTIES FOLDER "third_party")
+    set_target_properties(gtest_main PROPERTIES FOLDER "third_party")
 endif()
 
 ###########################################################
@@ -901,6 +910,8 @@
     if (NOT TARGET benchmark::benchmark)
         set(BENCHMARK_ENABLE_TESTING FALSE CACHE BOOL FALSE FORCE)
         add_subdirectory(${THIRD_PARTY_DIR}/benchmark)
+        set_target_properties(benchmark PROPERTIES FOLDER "third_party")
+        set_target_properties(benchmark_main PROPERTIES FOLDER "third_party")
     endif()
 
     if (NOT TARGET glslang)
diff --git a/third_party/astc-encoder/CMakeLists.txt b/third_party/astc-encoder/CMakeLists.txt
index e8a5646..06d23c5 100644
--- a/third_party/astc-encoder/CMakeLists.txt
+++ b/third_party/astc-encoder/CMakeLists.txt
@@ -39,7 +39,6 @@
 
 set_target_properties(astc-encoder PROPERTIES
     POSITION_INDEPENDENT_CODE 1
-    FOLDER "Core"
 )
 
 target_include_directories(astc-encoder
diff --git a/third_party/llvm-10.0/CMakeLists.txt b/third_party/llvm-10.0/CMakeLists.txt
index c5e1a86..e0a4416 100644
--- a/third_party/llvm-10.0/CMakeLists.txt
+++ b/third_party/llvm-10.0/CMakeLists.txt
@@ -1199,7 +1199,6 @@
 
 set_target_properties(llvm PROPERTIES
     POSITION_INDEPENDENT_CODE 1
-    FOLDER "LLVM"
 )
 
 target_include_directories(llvm
diff --git a/third_party/llvm-subzero/CMakeLists.txt b/third_party/llvm-subzero/CMakeLists.txt
index eb08fc4..03b63b7 100644
--- a/third_party/llvm-subzero/CMakeLists.txt
+++ b/third_party/llvm-subzero/CMakeLists.txt
@@ -229,7 +229,6 @@
 
 set_target_properties(llvm-subzero PROPERTIES
     POSITION_INDEPENDENT_CODE 1
-    FOLDER "Subzero"
 )
 
 target_include_directories(llvm-subzero
diff --git a/third_party/subzero/CMakeLists.txt b/third_party/subzero/CMakeLists.txt
index 031a6d3..ab337a7 100644
--- a/third_party/subzero/CMakeLists.txt
+++ b/third_party/subzero/CMakeLists.txt
@@ -93,7 +93,6 @@
 
 set_target_properties(subzero PROPERTIES
     POSITION_INDEPENDENT_CODE 1
-    FOLDER "Subzero"
 )
 
 target_include_directories(subzero