Code cleanup.

com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/Messages.java

diff --git a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/Messages.java b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/Messages.java
index 07f30b4..92f36f1 100644
--- a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/Messages.java
+++ b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/Messages.java
@@ -27,6 +27,7 @@
   public static String missingFieldNumber;
   public static String multiplePackages;
   public static String nonProto2;
+  public static String scopingError;
   public static String unrecognizedSyntaxIdentifier;
 
   static {

com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/Messages.properties

diff --git a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/Messages.properties b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/Messages.properties
index 1faeb4b..7f8eb32 100644
--- a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/Messages.properties
+++ b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/Messages.properties
@@ -5,9 +5,10 @@
 expectedTrueOrFalse = Expected "true" or "false".
 fieldNumberAlreadyUsed = Field number %d has already been used in \"%s\" by field \"%s\".
 fieldNumbersMustBePositive = Field numbers must be positive integers.
-importingNonProto2 = Importing non-proto2 file (directly or indirectly.) This may result in errors related to unresolved references.
+importingNonProto2 = Importing non-proto2 file. This may result in errors related to unresolved references.
 importNotFound = Import \"%s\" was not found.
 missingFieldNumber = Missing field number.
 multiplePackages = Multiple package definitions.
 nonProto2 = Deprecated syntax.  This parser only recognizes \"proto2\".
+scopingError = It may be caused by an imported non-proto2 file.
 unrecognizedSyntaxIdentifier = Unrecognized syntax identifier \"%s\".  This parser only recognizes \"proto2\".

com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/ProtobufResourceValidator.java

diff --git a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/ProtobufResourceValidator.java b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/ProtobufResourceValidator.java
index 8b5be54..e16ee7c 100644
--- a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/ProtobufResourceValidator.java
+++ b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/validation/ProtobufResourceValidator.java
@@ -10,7 +10,7 @@
 
 import static com.google.common.collect.Lists.newArrayListWithExpectedSize;
 import static com.google.common.collect.Maps.newHashMap;
-import static com.google.eclipse.protobuf.validation.Messages.importingNonProto2;
+import static com.google.eclipse.protobuf.validation.Messages.*;
 import static org.eclipse.xtext.diagnostics.Severity.*;
 import static org.eclipse.xtext.validation.AbstractInjectableValidator.CURRENT_LANGUAGE_NAME;
 import static org.eclipse.xtext.validation.CancelableDiagnostician.CANCEL_INDICATOR;
@@ -72,7 +72,8 @@
             severity = WARNING;
             ProtobufLinkingDiagnostic d = (ProtobufLinkingDiagnostic) error;
             if (!d.getMessage().endsWith(".")) d.appendToMessage(".");
-            d.appendToMessage(" It may be caused by a non-proto2 file imported directly or indirectly.");
+            d.appendToMessage(" ");
+            d.appendToMessage(scopingError);
           }
           issueFromXtextResourceDiagnostic(error, severity, acceptor);
         }