Fix Installations CMake, and remove absl dependency in the test

Author: a-maurice

installations/CMakeLists.txt

@@ -41,13 +41,6 @@ else()
       "${desktop_SRCS}")
 endif()
 
-if(ANDROID OR IOS OR use_stub)
-  set(additional_link_LIB)
-else()
-  set(additional_link_LIB
-      firebase_installations_desktop_impl)
-endif()
-
 add_library(firebase_installations STATIC
     ${common_SRCS}
     ${installations_platform_SRCS})
@@ -58,8 +51,6 @@ set_property(TARGET firebase_installations PROPERTY FOLDER "Firebase Cpp")
 target_link_libraries(firebase_installations
   PUBLIC
     firebase_app
-  PRIVATE
-    ${additional_link_LIB}
 )
 # Public headers all refer to each other relative to the src/include directory,
 # while private headers are relative to the entire C++ SDK directory.

installations/tests/CMakeLists.txt

@@ -0,0 +1,23 @@
+# Copyright 2021 Google LLC
+# 
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+firebase_cpp_cc_test(
+  firebase_installations_test
+  SOURCES
+    ${FIREBASE_SOURCE_DIR}/installations/tests/installations_test.cc
+  DEPENDS
+    firebase_app_for_testing
+    firebase_installations
+    firebase_testing
+)

installations/tests/installations_test.cc

@@ -104,21 +104,21 @@ class InstallationsTest : public ::testing::Test {
 
 // Check SetUp and TearDown working well.
 TEST_F(InstallationsTest, InitializeAndTerminate) {
-  auto installations =
-      absl::WrapUnique(Installations::GetInstance(firebase_app_));
+  auto* installations = Installations::GetInstance(firebase_app_);
   EXPECT_THAT(installations, NotNull());
+  delete installations;
 }
 
 TEST_F(InstallationsTest, InitializeTwice) {
-  auto installations1 =
-      absl::WrapUnique(Installations::GetInstance(firebase_app_));
+  auto* installations1 = Installations::GetInstance(firebase_app_);
   EXPECT_THAT(installations1, NotNull());
 
-  auto installations2 =
-      absl::WrapUnique(Installations::GetInstance(firebase_app_));
+  auto* installations2 = Installations::GetInstance(firebase_app_);
   EXPECT_THAT(installations2, NotNull());
 
   EXPECT_EQ(installations1, installations2);
+  delete installations1;
+  delete installations2;
 }
 
 TEST_F(InstallationsTest, GetId) {