Sort input method list as the sequence as XKB, M17n, T13, CJK.

BUG=432662
TEST=Verified on linux_chromeos.

Review URL: https://codereview.chromium.org/722183002

Cr-Commit-Position: refs/heads/master@{#304033}
(cherry picked from commit 09194f83919025a67a0eaf3b610fa91f6e14e480)

Review URL: https://codereview.chromium.org/736743004

Cr-Commit-Position: refs/branch-heads/2171@{#431}
Cr-Branched-From: 267aeeb8d85c8503a7fd12bd14654b8ea78d3974-refs/heads/master@{#297060}

2 files changed, 45 insertions, 13 deletions

diff --git a/chromeos/ime/component_extension_ime_manager.cc b/chromeos/ime/component_extension_ime_manager.cc
index feb0347..49bd813 100644
--- a/chromeos/ime/component_extension_ime_manager.cc
+++ b/chromeos/ime/component_extension_ime_manager.cc
@@ -55,6 +55,27 @@ const char* kLoginLayoutWhitelist[] = {
   "us(intl)"
 };
 
+// Gets the input method category according to the given input method id.
+// This is used for sorting a list of input methods.
+int GetInputMethodCategory(const std::string& id) {
+  const std::string engine_id =
+      chromeos::extension_ime_util::GetComponentIDByInputMethodID(id);
+  if (StartsWithASCII(engine_id, "xkb:", true))
+    return 0;
+  if (StartsWithASCII(engine_id, "vkd_", true))
+    return 1;
+  if (engine_id.find("-t-i0-") != std::string::npos &&
+      !StartsWithASCII(engine_id, "zh-", true)) {
+    return 2;
+  }
+  return 3;
+}
+
+bool InputMethodCompare(const input_method::InputMethodDescriptor& im1,
+                        const input_method::InputMethodDescriptor& im2) {
+  return GetInputMethodCategory(im1.id()) < GetInputMethodCategory(im2.id());
+}
+
 } // namespace
 
 ComponentExtensionEngine::ComponentExtensionEngine() {
@@ -164,6 +185,7 @@ input_method::InputMethodDescriptors
               ime.input_view_url));
     }
   }
+  std::stable_sort(result.begin(), result.end(), InputMethodCompare);
   return result;
 }
 
diff --git a/chromeos/ime/component_extension_ime_manager_unittest.cc b/chromeos/ime/component_extension_ime_manager_unittest.cc
index 9e8bdb3..840f3c4 100644
--- a/chromeos/ime/component_extension_ime_manager_unittest.cc
+++ b/chromeos/ime/component_extension_ime_manager_unittest.cc
@@ -28,24 +28,24 @@ class ComponentExtensionIMEManagerTest : public testing::Test {
     ext1.path = base::FilePath("ext1_file_path");
 
     ComponentExtensionEngine ext1_engine1;
-    ext1_engine1.engine_id = "ext1_engine1_engine_id";
+    ext1_engine1.engine_id = "zh-t-i0-pinyin";
     ext1_engine1.display_name = "ext1_engine_1_display_name";
-    ext1_engine1.language_codes.push_back("en");
+    ext1_engine1.language_codes.push_back("zh-CN");
     ext1_engine1.layouts.push_back("us");
     ext1.engines.push_back(ext1_engine1);
 
     ComponentExtensionEngine ext1_engine2;
-    ext1_engine2.engine_id = "ext1_engine2_engine_id";
+    ext1_engine2.engine_id = "mozc_us";
     ext1_engine2.display_name = "ext1_engine2_display_name";
-    ext1_engine2.language_codes.push_back("en");
+    ext1_engine2.language_codes.push_back("jp");
     ext1_engine2.layouts.push_back("us");
     ext1.engines.push_back(ext1_engine2);
 
     ComponentExtensionEngine ext1_engine3;
-    ext1_engine3.engine_id = "ext1_engine3_engine_id";
+    ext1_engine3.engine_id = "xkb:ru::rus";
     ext1_engine3.display_name = "ext1_engine3_display_name";
-    ext1_engine3.language_codes.push_back("ja");
-    ext1_engine3.layouts.push_back("us");
+    ext1_engine3.language_codes.push_back("ru");
+    ext1_engine3.layouts.push_back("ru");
     ext1.engines.push_back(ext1_engine3);
 
     ime_list_.push_back(ext1);
@@ -56,24 +56,24 @@ class ComponentExtensionIMEManagerTest : public testing::Test {
     ext2.path = base::FilePath("ext2_file_path");
 
     ComponentExtensionEngine ext2_engine1;
-    ext2_engine1.engine_id = "ext2_engine1_engine_id";
+    ext2_engine1.engine_id = "vkd_ru_phone_aatseel";
     ext2_engine1.display_name = "ext2_engine_1_display_name";
-    ext2_engine1.language_codes.push_back("en");
+    ext2_engine1.language_codes.push_back("ru");
     ext2_engine1.layouts.push_back("us");
     ext2.engines.push_back(ext2_engine1);
 
     ComponentExtensionEngine ext2_engine2;
-    ext2_engine2.engine_id = "ext2_engine2_engine_id";
+    ext2_engine2.engine_id = "vkd_vi_telex";
     ext2_engine2.display_name = "ext2_engine2_display_name";
     ext2_engine2.language_codes.push_back("hi");
     ext2_engine2.layouts.push_back("us");
     ext2.engines.push_back(ext2_engine2);
 
     ComponentExtensionEngine ext2_engine3;
-    ext2_engine3.engine_id = "ext2_engine3_engine_id";
+    ext2_engine3.engine_id = "xkb:us::eng";
     ext2_engine3.display_name = "ext2_engine3_display_name";
-    ext2_engine3.language_codes.push_back("ja");
-    ext2_engine3.layouts.push_back("jp");
+    ext2_engine3.language_codes.push_back("us");
+    ext2_engine3.layouts.push_back("us");
     ext2.engines.push_back(ext2_engine3);
 
     ime_list_.push_back(ext2);
@@ -191,6 +191,16 @@ TEST_F(ComponentExtensionIMEManagerTest, GetAllIMEAsInputMethodDescriptor) {
     total_ime_size += ime_list_[i].engines.size();
   }
   EXPECT_EQ(total_ime_size, descriptors.size());
+
+  // Verify order
+  for (size_t i = 0; i < descriptors.size(); ++i) {
+    const input_method::InputMethodDescriptor& d = descriptors[i];
+    if (i < 2) {
+      EXPECT_TRUE(d.id().find("xkb:") != std::string::npos);
+    } else if (i >= 2 && i < 4) {
+      EXPECT_TRUE(d.id().find("vkd_") != std::string::npos);
+    }
+  }
 }
 
 }  // namespace