[gnumeric] xls: fuzzed file fix re trend lines.

[Morten Welinder <mortenw src gnome org>]

commit aa8061ee6fcba580968d4752f62dc6b2460cece2
Author: Morten Welinder <terra gnome org>
Date:   Sat Jun 20 12:02:53 2015 -0400

    xls: fuzzed file fix re trend lines.

 NEWS                     |    2 +-
 plugins/excel/ChangeLog  |    3 +++
 plugins/excel/ms-chart.c |    1 +
 3 files changed, 5 insertions(+), 1 deletions(-)
---
diff --git a/NEWS b/NEWS
index 429f3bb..3f50210 100644
--- a/NEWS
+++ b/NEWS
@@ -27,7 +27,7 @@ Morten:
          [#749236] [#749240] [#749234] [#749235] [#749271] [#749270]
          [#749424] [#749917] [#749919] [#750043] [#750044] [#750046]
          [#750811] [#750810] [#750857] [#750864] [#750862] [#750858]
-         [#751126] [#751254]
+         [#751126] [#751254] [#751253]
        * Make solver check linearity of model.
        * Fix xls saving of marker style.  [#749185]
        * Make compilation with clang work again.  [#749138]
diff --git a/plugins/excel/ChangeLog b/plugins/excel/ChangeLog
index 23b14a1..786b271 100644
--- a/plugins/excel/ChangeLog
+++ b/plugins/excel/ChangeLog
@@ -1,5 +1,8 @@
 2015-06-20  Morten Welinder  <terra gnome org>
 
+       * ms-chart.c (trendlimits): Bail if we don't have a series.  Fixes
+       #751253.
+
        * ms-excel-read.c (sst_read_string): Handle errors from
        excel_get_chars.  Fixes #751254.
 
diff --git a/plugins/excel/ms-chart.c b/plugins/excel/ms-chart.c
index 982b471..6bb845a 100644
--- a/plugins/excel/ms-chart.c
+++ b/plugins/excel/ms-chart.c
@@ -1927,6 +1927,7 @@ BC_R(trendlimits)(XLChartHandler const *handle,
        double min, max;
        gboolean skip_invalid;
 
+       XL_CHECK_CONDITION_VAL (s->currentSeries, FALSE);
        XL_CHECK_CONDITION_VAL (q->length >= 17, FALSE);
        min = GSF_LE_GET_DOUBLE (q->data);
        max = GSF_LE_GET_DOUBLE (q->data + 8);