correctly parse tag in the beginning of doc comment

compiler/frontend/src/org/jetbrains/kotlin/kdoc/lexer/KDoc.flex

@@ -59,7 +59,7 @@ CODE_LINK=\[{CODE_LINK_START}{CODE_LINK_CHAR}*\]
 %%
 
 
-<YYINITIAL> "/**"                         { yybegin(CONTENTS);
+<YYINITIAL> "/**"                         { yybegin(CONTENTS_BEGINNING);
                                             return KDocTokens.START;            }
 "*"+ "/"                                  { if (isLastToken()) return KDocTokens.END;
                                             else return KDocTokens.TEXT; }

compiler/frontend/src/org/jetbrains/kotlin/kdoc/lexer/_KDocLexer.java

@@ -1,20 +1,4 @@
-/*
- * Copyright 2010-2015 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-/* The following code was generated by JFlex 1.4.3 on 1/19/15 8:28 PM */
+/* The following code was generated by JFlex 1.4.3 on 2/2/15 2:35 PM */
 
 package org.jetbrains.kotlin.kdoc.lexer;
 
@@ -28,7 +12,7 @@ import java.lang.Character;
 /**
  * This class is a scanner generated by 
  * <a href="http://www.jflex.de/">JFlex</a> 1.4.3
- * on 1/19/15 8:28 PM from the specification file
+ * on 2/2/15 2:35 PM from the specification file
  * <tt>/Users/yole/jetbrains/kotlin/compiler/frontend/src/org/jetbrains/kotlin/kdoc/lexer/KDoc.flex</tt>
  */
 class _KDocLexer implements FlexLexer {
@@ -582,37 +566,37 @@ class _KDocLexer implements FlexLexer {
         }
           }
         case 13: break;
+        case 11: 
+          { yybegin(CONTENTS_BEGINNING);
+                                            return KDocTokens.START;
+          }
+        case 14: break;
         case 7: 
           { yybegin(CONTENTS);
         return KDocTokens.TEXT_OR_LINK;
           }
-        case 14: break;
+        case 15: break;
         case 8: 
           { if (isLastToken()) return KDocTokens.END;
                                             else return KDocTokens.TEXT;
           }
-        case 15: break;
+        case 16: break;
         case 5: 
           { yybegin(CONTENTS);
         return KDocTokens.TEXT;
           }
-        case 16: break;
+        case 17: break;
         case 6: 
           { if (yytextContainLineBreaks()) {
             yybegin(LINE_BEGINNING);
         }
         return TokenType.WHITE_SPACE;
           }
-        case 17: break;
+        case 18: break;
         case 12: 
           { yybegin(CONTENTS);
                   return KDocTokens.MARKDOWN_LINK;
           }
-        case 18: break;
-        case 11: 
-          { yybegin(CONTENTS);
-                                            return KDocTokens.START;
-          }
         case 19: break;
         case 10: 
           { yybegin(TAG_BEGINNING);

compiler/testData/psi/kdoc/ParamTagAtStart.kt

@@ -0,0 +1 @@
+/** @param a this is a */

compiler/testData/psi/kdoc/ParamTagAtStart.txt

@@ -0,0 +1,14 @@
+JetFile: ParamTagAtStart.kt
+  PACKAGE_DIRECTIVE
+    <empty list>
+  KDoc
+    PsiElement(KDOC_START)('/**')
+    KDOC_SECTION
+      PsiElement(KDOC_TEXT)(' ')
+      KDOC_TAG
+        PsiElement(KDOC_TAG_NAME)('@param')
+        PsiWhiteSpace(' ')
+        KDOC_LINK
+          PsiElement(KDOC_TEXT_OR_LINK)('a')
+        PsiElement(KDOC_TEXT)(' this is a ')
+    PsiElement(KDOC_END)('*/')

compiler/tests/org/jetbrains/kotlin/parsing/JetParsingTestGenerated.java

@@ -1091,6 +1091,12 @@ public class JetParsingTestGenerated extends AbstractJetParsingTest {
                 doParsingTest(fileName);
             }
 
+            @TestMetadata("ParamTagAtStart.kt")
+            public void testParamTagAtStart() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("compiler/testData/psi/kdoc/ParamTagAtStart.kt");
+                doParsingTest(fileName);
+            }
+
             @TestMetadata("ReturnWithBrackets.kt")
             public void testReturnWithBrackets() throws Exception {
                 String fileName = JetTestUtils.navigationMetadata("compiler/testData/psi/kdoc/ReturnWithBrackets.kt");