Avoid overwrite of the error message in AbortFn

The AbortFn() used to overwrite the error message, hiding the real
failure reported in ErrorAbort(). And we will miss the failure in
the script patterns like 'blockimageupdate() || abort()'

We will ensure there's one line break at the end of ErrorAbort's
error message; and append to the existing error message when calling
abort().

Test: Message from ErrorAbort shows up in the log
Change-Id: I3aebd06629c5129330250c7fe5e8cdead2ae85bc
diff --git a/updater/install.cpp b/updater/install.cpp
index b83d30f..eef252e 100644
--- a/updater/install.cpp
+++ b/updater/install.cpp
@@ -268,7 +268,7 @@
 
   int64_t size;
   if (!android::base::ParseInt(fs_size, &size)) {
-    return ErrorAbort(state, kArgsParsingFailure, "%s: failed to parse int in %s\n", name,
+    return ErrorAbort(state, kArgsParsingFailure, "%s: failed to parse int in %s", name,
                       fs_size.c_str());
   }
 
@@ -352,12 +352,12 @@
 
   double frac;
   if (!android::base::ParseDouble(frac_str.c_str(), &frac)) {
-    return ErrorAbort(state, kArgsParsingFailure, "%s: failed to parse double in %s\n", name,
+    return ErrorAbort(state, kArgsParsingFailure, "%s: failed to parse double in %s", name,
                       frac_str.c_str());
   }
   int sec;
   if (!android::base::ParseInt(sec_str.c_str(), &sec)) {
-    return ErrorAbort(state, kArgsParsingFailure, "%s: failed to parse int in %s\n", name,
+    return ErrorAbort(state, kArgsParsingFailure, "%s: failed to parse int in %s", name,
                       sec_str.c_str());
   }
 
@@ -380,7 +380,7 @@
 
   double frac;
   if (!android::base::ParseDouble(frac_str.c_str(), &frac)) {
-    return ErrorAbort(state, kArgsParsingFailure, "%s: failed to parse double in %s\n", name,
+    return ErrorAbort(state, kArgsParsingFailure, "%s: failed to parse double in %s", name,
                       frac_str.c_str());
   }
 
@@ -574,8 +574,8 @@
 
   size_t bytes;
   if (!android::base::ParseUint(bytes_str.c_str(), &bytes)) {
-    return ErrorAbort(state, kArgsParsingFailure, "%s(): can't parse \"%s\" as byte count\n\n",
-                      name, bytes_str.c_str());
+    return ErrorAbort(state, kArgsParsingFailure, "%s(): can't parse \"%s\" as byte count", name,
+                      bytes_str.c_str());
   }
 
   // Skip the cache size check if the update is a retry.