Fix Truth dependencies

The used version of Truth indirectly depends on diffutils. Add it
similarly as we did for Gerrit core (see I80527c9ea4). Gerrit core also
specifies Guava as runtime dependence, so do it here too.

Change-Id: I3d106f3b990fa4447ac772cad4e2c4b3c2b50811
diff --git a/WORKSPACE b/WORKSPACE
index 47e3966..3a07abe 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -116,6 +116,13 @@
     sha1 = "b5768f644b114e6cf5c3962c2ebcb072f788dcbb",
 )
 
+# Indirect dependency of truth
+maven_jar(
+    name = "diffutils",
+    artifact = "com.googlecode.java-diff-utils:diffutils:1.3.0",
+    sha1 = "7e060dd5b19431e6d198e91ff670644372f60fbd",
+)
+
 maven_jar(
     name = "soy",
     artifact = "com.google.template:soy:2018-03-14",
diff --git a/javatests/com/google/gitiles/BUILD b/javatests/com/google/gitiles/BUILD
index 73b662c..8e18655 100644
--- a/javatests/com/google/gitiles/BUILD
+++ b/javatests/com/google/gitiles/BUILD
@@ -16,7 +16,7 @@
         "//java/com/google/gitiles:servlet",
         "//lib:jsr305",
         "//lib:servlet-api_2_5",
-        "//lib:truth",
+        "//lib/truth",
         "//lib/jgit:junit",
         "//lib/junit",
     ],
@@ -38,7 +38,7 @@
         "//java/com/google/gitiles:servlet",
         ":testutil",
         "//lib:servlet-api_2_5",
-        "//lib:truth",
+        "//lib/truth",
         "//lib/jgit:junit",
         "//lib/junit",
     ],
diff --git a/lib/BUILD b/lib/BUILD
index 110865c..9aef1e0 100644
--- a/lib/BUILD
+++ b/lib/BUILD
@@ -17,7 +17,6 @@
     "jsr305",
     "servlet-api_2_5",
     "servlet-api_3_0",
-    "truth",
     "gson",
     "guava",
     "prettify",
diff --git a/lib/truth/BUILD b/lib/truth/BUILD
new file mode 100644
index 0000000..22b79cf
--- /dev/null
+++ b/lib/truth/BUILD
@@ -0,0 +1,16 @@
+java_library(
+    name = "truth",
+    visibility = ["//visibility:public"],
+    exports = ["@truth//jar"],
+    runtime_deps = [
+        ":diffutils",
+        "//lib:guava",
+        "//lib/junit",
+    ],
+)
+
+java_library(
+    name = "diffutils",
+    visibility = ["//visibility:private"],
+    exports = ["@diffutils//jar"],
+)