Added escaping/unescaping signatures when saving/loading from annotations.

compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kt/KotlinSignatureAnnotation.java

@@ -16,6 +16,7 @@
 
 package org.jetbrains.jet.lang.resolve.java.kt;
 
+import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.psi.PsiAnnotation;
 import com.intellij.psi.PsiMethod;
 import org.jetbrains.annotations.NotNull;
@@ -36,7 +37,7 @@ public class KotlinSignatureAnnotation extends PsiAnnotationWrapper {
 
     public String signature() {
         if (signature == null) {
-            signature = getStringAttribute(JvmStdlibNames.KOTLIN_SIGNATURE_VALUE_METHOD, "");
+            signature = StringUtil.unescapeStringCharacters(getStringAttribute(JvmStdlibNames.KOTLIN_SIGNATURE_VALUE_METHOD, ""));
         }
         return signature;
     }

idea/src/org/jetbrains/jet/plugin/codeInsight/EditSignatureBalloon.java

@@ -29,6 +29,7 @@ import com.intellij.openapi.ui.popup.JBPopupAdapter;
 import com.intellij.openapi.ui.popup.JBPopupFactory;
 import com.intellij.openapi.ui.popup.LightweightWindowEvent;
 import com.intellij.openapi.util.SystemInfo;
+import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.openapi.wm.IdeFocusManager;
 import com.intellij.psi.JavaPsiFacade;
 import com.intellij.psi.PsiDocumentManager;
@@ -223,7 +224,7 @@ class EditSignatureBalloon {
 
     static PsiNameValuePair[] signatureToNameValuePairs(@NotNull Project project, @NotNull String signature) {
         return JavaPsiFacade.getElementFactory(project).createAnnotationFromText(
-                        "@" + KotlinSignatureInJavaMarkerProvider.KOTLIN_SIGNATURE_ANNOTATION + "(value=\"" + signature + "\")", null)
-                        .getParameterList().getAttributes();
+                "@" + KotlinSignatureInJavaMarkerProvider.KOTLIN_SIGNATURE_ANNOTATION
+                + "(value=\"" + StringUtil.escapeStringCharacters(signature) + "\")", null).getParameterList().getAttributes();
     }
 }

idea/src/org/jetbrains/jet/plugin/codeInsight/KotlinSignatureInJavaMarkerProvider.java

@@ -28,6 +28,7 @@ import com.intellij.openapi.actionSystem.PlatformDataKeys;
 import com.intellij.openapi.editor.Editor;
 import com.intellij.openapi.fileEditor.OpenFileDescriptor;
 import com.intellij.openapi.project.Project;
+import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.psi.*;
 import com.intellij.util.Function;
@@ -93,7 +94,7 @@ public class KotlinSignatureInJavaMarkerProvider implements LineMarkerProvider {
         PsiNameValuePair pair = kotlinSignatureAnnotation.getParameterList().getAttributes()[0];
         PsiAnnotationMemberValue value = pair.getValue();
         return value == null ? "null" : value instanceof PsiLiteralExpression
-                                        ? ((PsiLiteralExpression) value).getValue().toString()
+                                        ? StringUtil.unescapeStringCharacters(((PsiLiteralExpression) value).getValue().toString())
                                         : value.getText();
     }