Make this docs more consistent with the rest of the docs present

activerecord/lib/active_record/connection_adapters/mysql_adapter.rb

@@ -208,13 +208,13 @@ module ActiveRecord
         true
       end
 
-      # Returns +true+, since this connection adapter supports prepared statement
+      # Returns true, since this connection adapter supports prepared statement
       # caching.
       def supports_statement_cache?
         true
       end
 
-      # Returns true.
+      # Returns true, since this connection adapter supports migrations.
       def supports_migrations? #:nodoc:
         true
       end
@@ -224,6 +224,7 @@ module ActiveRecord
         true
       end
 
+      # Returns true, since this connection adapter supports savepoints.
       def supports_savepoints? #:nodoc:
         true
       end

activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb

@@ -290,7 +290,7 @@ module ActiveRecord
         NATIVE_DATABASE_TYPES
       end
 
-      # Does PostgreSQL support migrations?
+      # Returns true, since this connection adapter supports migrations.
       def supports_migrations?
         true
       end
@@ -316,6 +316,7 @@ module ActiveRecord
         true
       end
 
+      # Returns true, since this connection adapter supports savepoints.
       def supports_savepoints?
         true
       end

activerecord/lib/active_record/connection_adapters/sqlite_adapter.rb

@@ -72,7 +72,7 @@ module ActiveRecord
         true
       end
 
-      # Returns true.
+      # Returns true, since this connection adapter supports migrations.
       def supports_migrations? #:nodoc:
         true
       end