Enforce max conversation starters.

The number of conversation starters should not exceed our stated max.
Note that this CL also updates names of some unittests which contained
"_" in their names (which is discouraged).

Bug: b:148246719
Change-Id: I01ea72c5ba5967ec489a170c5a6a799de56a731b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2031666Reviewed-by: Xiaohui Chen <xiaohuic@chromium.org>
Commit-Queue: David Black <dmblack@google.com>
Cr-Commit-Position: refs/heads/master@{#737116}

ash/assistant/assistant_suggestions_controller.cc

@@ -203,8 +203,12 @@ void AssistantSuggestionsController::FetchConversationStarters() {
           return;
         }
 
-        // Otherwise we transform our conversation starters into the type that
-        // is understood by the suggestions model...
+        // The number of conversation starters should not exceed our maximum.
+        while (conversation_starters.size() > kMaxNumOfConversationStarters)
+          conversation_starters.pop_back();
+
+        // We need to transform our conversation starters into the type that is
+        // understood by the suggestions model...
         std::vector<AssistantSuggestionPtr> suggestions;
         std::transform(
             conversation_starters.begin(), conversation_starters.end(),

chrome/browser/ui/ash/assistant/conversation_starters_parser_unittest.cc

@@ -27,14 +27,14 @@ void ExpectEqual(const ash::ConversationStarter& a,
 using ConversationStartersParserTest = ChromeAshTestBase;
 
 // Verifies handling of an empty response.
-TEST_F(ConversationStartersParserTest, Parse_EmptyResponse) {
+TEST_F(ConversationStartersParserTest, HandlesEmptyResponse) {
   const std::vector<ash::ConversationStarter> conversation_starters =
       ConversationStartersParser::Parse(std::string());
   EXPECT_TRUE(conversation_starters.empty());
 }
 
 // Verifies handling of a non-safe JSON response.
-TEST_F(ConversationStartersParserTest, Parse_JsonResponse) {
+TEST_F(ConversationStartersParserTest, HandlesJsonResponse) {
   const std::vector<ash::ConversationStarter> conversation_starters =
       ConversationStartersParser::Parse(R"(
         {
@@ -52,7 +52,7 @@ TEST_F(ConversationStartersParserTest, Parse_JsonResponse) {
 }
 
 // Verifies handling of a safe JSON response that is not recognized.
-TEST_F(ConversationStartersParserTest, Parse_SafeJsonResponse_Unrecognized) {
+TEST_F(ConversationStartersParserTest, HandlesUnrecognizedSafeJsonResponse) {
   const std::vector<ash::ConversationStarter> conversation_starters =
       ConversationStartersParser::Parse(R"()]}'
           {
@@ -83,7 +83,7 @@ TEST_F(ConversationStartersParserTest, Parse_SafeJsonResponse_Unrecognized) {
 // Verifies handling of a safe JSON response that is recognized.
 // Note that |label| is required, but |actionUrl|, |iconUrl|, and
 // |requiredPermissions| are optional.
-TEST_F(ConversationStartersParserTest, Parse_SafeJsonResponse_Recognized) {
+TEST_F(ConversationStartersParserTest, HandlesRecognizedSafeJsonResponse) {
   const std::vector<ash::ConversationStarter> conversation_starters =
       ConversationStartersParser::Parse(R"()]}'
           {
@@ -133,7 +133,7 @@ TEST_F(ConversationStartersParserTest, Parse_SafeJsonResponse_Recognized) {
 
 // Verifies that a conversation starter that does not specify a |label| is
 // omitted from the collection.
-TEST_F(ConversationStartersParserTest, Parse_MissingLabel) {
+TEST_F(ConversationStartersParserTest, HandlesMissingLabel) {
   const std::vector<ash::ConversationStarter> conversation_starters =
       ConversationStartersParser::Parse(R"()]}'
           {
@@ -151,7 +151,7 @@ TEST_F(ConversationStartersParserTest, Parse_MissingLabel) {
 
 // Verifies that a conversation starter that specifies a required permission
 // that is not recognized is marked as requiring an unknown permission.
-TEST_F(ConversationStartersParserTest, Parse_UnknownPermission) {
+TEST_F(ConversationStartersParserTest, HandlesUnknownPermission) {
   const std::vector<ash::ConversationStarter> conversation_starters =
       ConversationStartersParser::Parse(R"()]}'
           {