GN (android): Append ".cr" to component .so's to avoid zygote lib collisions

With this, ChromePublic now launches with is_component_build = true

BUG=500882

Review URL: https://codereview.chromium.org/1236543004

Cr-Original-Commit-Position: refs/heads/master@{#338612}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: a2daf08ffddf4549160f3925383b457a2eb03c7f

config/android/config.gni

@@ -162,7 +162,7 @@ if (is_android) {
   android_gdbserver =
       "$android_ndk_root/prebuilt/$android_prebuilt_arch/gdbserver/gdbserver"
 
-  # libc++ stuff ---------------------------------------------------------------
+  # Toolchain stuff ------------------------------------------------------------
 
   android_libcpp_root = "$android_ndk_root/sources/cxx-stl/llvm-libc++"
   if (component_mode == "shared_library") {
@@ -171,6 +171,10 @@ if (is_android) {
     android_libcpp_library = "c++_static"
   }
 
+  # By appending .cr, we prevent name collisions with libraries already
+  # loaded by the Android zygote.
+  android_product_extension = ".cr.so"
+
   # ABI ------------------------------------------------------------------------
 
   if (current_cpu == "x86") {

config/android/rules.gni

@@ -1432,20 +1432,22 @@ template("android_apk") {
              "Relocation packing requires use of the" + " Chromium linker.")
     }
 
-    _native_libs = []
     if (is_component_build) {
       _native_libs += [ "$root_out_dir/lib.stripped/libc++_shared.so" ]
       _chromium_linker_dep += [ "//build/android:cpplib_stripped" ]
     }
+
+    # Allow native_libs to be in the form "foo.so" or "foo.cr.so"
+    _first_ext_removed =
+        process_file_template(invoker.native_libs, "{{source_name_part}}")
     _native_libs += process_file_template(
-            invoker.native_libs,
-            "$root_build_dir/lib.stripped/{{source_file_part}}")
+            _first_ext_removed,
+            "$root_build_dir/lib.stripped/{{source_name_part}}$android_product_extension")
 
     _native_libs_dir = base_path + "/libs"
 
     if (_use_chromium_linker) {
-      _native_libs +=
-          [ "$root_build_dir/lib.stripped/libchromium_android_linker.so" ]
+      _native_libs += [ "$root_build_dir/lib.stripped/libchromium_android_linker$android_product_extension" ]
     }
 
     _enable_relocation_packing = false
@@ -1656,7 +1658,7 @@ template("android_apk") {
 
       skip_packing_list = [
         "gdbserver",
-        "libchromium_android_linker.so",
+        "libchromium_android_linker$android_product_extension",
       ]
 
       enable_packing_arg = 0
@@ -1940,7 +1942,7 @@ template("unittest_apk") {
   if (defined(invoker.unittests_binary)) {
     unittests_binary = invoker.unittests_binary
   } else {
-    unittests_binary = "lib" + test_suite_name + ".so"
+    unittests_binary = "lib${test_suite_name}${android_product_extension}"
   }
 
   if (defined(invoker.apk_name)) {

toolchain/android/BUILD.gn

@@ -69,6 +69,7 @@ template("android_gcc_toolchain") {
     replace_command = "if ! cmp -s $temp_stripped_soname $stripped_soname; then mv $temp_stripped_soname $stripped_soname; fi"
     postsolink = "$strip_command && $replace_command"
     solink_outputs = [ stripped_soname ]
+    default_output_extension = android_product_extension
 
     # We make the assumption that the gcc_toolchain will produce an exe with
     # the following definition.

toolchain/gcc_toolchain.gni

@@ -160,6 +160,9 @@ template("gcc_toolchain") {
       # overrides it (in which case {{output_extension}} will be what the target
       # specifies).
       default_output_extension = ".so"
+      if (defined(invoker.default_output_extension)) {
+        default_output_extension = invoker.default_output_extension
+      }
 
       output_prefix = "lib"