Remove support for STLPort and deprecate support for gnustl on Android

Author: var-const

app/src/include/firebase/app.h

@@ -55,9 +55,9 @@ namespace internal {
 class AppInternal;
 }  // namespace internal
 
-#ifdef _STLPORT_VERSION
-#warning "Firebase support for STLPort is deprecated and will be removed in \
-  the next major release. Please use libc++ instead."
+#if FIREBASE_PLATFORM_ANDROID && defined(__GLIBCXX__)
+#warning "Firebase support for gnustl is deprecated and will be removed in \
+    the next major release. Please use libc++ instead."
 #endif
 
 /// @brief Reports whether a Firebase module initialized successfully.

build_scripts/android/build.sh

@@ -5,7 +5,7 @@ sourcepath=$2
 stl=$3
 
 if [[ -z "${buildpath}" || -z "${sourcepath}" ]]; then
-    echo "Usage: $0 <build path> <source path> [c++|gnustl|stlport]"
+    echo "Usage: $0 <build path> <source path> [c++|gnustl]"
     exit 1
 fi
 
@@ -14,11 +14,11 @@ if [[ ! -d "${sourcepath}" ]]; then
     exit 2
 fi
 
-if [[ "${stl}" == "c++" || "${stl}" == "gnustl" || "${stl}" == "stlport" ]]; then
+if [[ "${stl}" == "c++" || "${stl}" == "gnustl" ]]; then
     export FIREBASE_ANDROID_STL="${stl}"_static
 elif [[ ! -z "${stl}" ]]; then
     echo "Invalid STL specified."
-    echo "Valid STLs are: 'c++' (default), 'gnustl', or 'stlport'"
+    echo "Valid STLs are: 'c++' (default) or 'gnustl'"
     exit 2
 fi
 

build_scripts/android/package.sh

@@ -1,6 +1,6 @@
 #!/bin/bash -e
 
-readonly -a allowed_stl_variants=("c++" "gnustl" "stlport")
+readonly -a allowed_stl_variants=("c++" "gnustl")
 builtpath=$1
 packagepath=$2
 stl=$3

build_scripts/desktop/get_variant.sh

@@ -125,9 +125,6 @@ for c in $(echo "${filename}" | tr "[:upper:]" "[:lower:]" | tr "_.-" "\n\n\n");
 	gnustl)
 	    stl=gnustl
         ;;
-	stlport)
-	    stl=stlport
-        ;;
 	cxx11)
 	    linux_abi=cxx11
         ;;

release_build_files/readme.md

@@ -363,8 +363,12 @@ code.
 ## Release Notes
 
 ### 8.0.0
-    
 -   Changes
+    -   General (Android): Firebase no longer supports STLPort. Please
+        [use libc++ instead](https://developer.android.com/ndk/guides/cpp-support#cs).
+    -   General (Android): Firebase support for gnustl (also known as libstdc++)
+        is deprecated and will be removed in the next major release. Please use
+        libc++ instead.
     -   Instance Id: Removed support for the previously-deprecated Instance ID SDK.
     -   Remote Config: The previously-deprecated static methods have been removed.
         Please use the new instance-based `firebase::remote_config::RemoteConfig`