Change default value of tag filters to empty (#643)

Fixes #270.

Author: kho

Diff for: tensorboard/plugins/audio/tf_audio_dashboard/tf-audio-dashboard.html

@@ -124,7 +124,7 @@ <h3>No audio data was found.</h3>
 
         _tagFilter: {
           type: String,  // upward bound from paper-input
-          value: '.*',
+          value: '',
         },
         _categories: {
           type: Array,

Diff for: tensorboard/plugins/distribution/tf_distribution_dashboard/tf-distribution-dashboard.html

@@ -150,7 +150,7 @@ <h3>No distribution data was found.</h3>
 
         _tagFilter: {
           type: String,  // upward bound from paper-input
-          value: '.*',
+          value: '',
         },
         _categories: {
           type: Array,

Diff for: tensorboard/plugins/histogram/tf_histogram_dashboard/tf-histogram-dashboard.html

@@ -162,7 +162,7 @@ <h3>No histogram data was found.</h3>
 
         _tagFilter: {
           type: String,  // upward bound from paper-input
-          value: '.*',
+          value: '',
         },
         _categories: {
           type: Array,

Diff for: tensorboard/plugins/image/tf_image_dashboard/tf-image-dashboard.html

@@ -136,7 +136,7 @@ <h3>No image data was found.</h3>
 
         _tagFilter: {
           type: String,  // upward bound from paper-input
-          value: '.*',
+          value: '',
         },
         _categories: {
           type: Array,

Diff for: tensorboard/plugins/pr_curve/tf_pr_curve_dashboard/tf-pr-curve-dashboard.html

@@ -181,7 +181,7 @@ <h3>No precision–recall curve data was found.</h3>
       _dataNotFound: Boolean,
       _tagFilter: {
         type: String,  // upward bound from paper-input
-        value: '.*',
+        value: '',
       },
       _categories: {
         type: Array,

Diff for: tensorboard/plugins/scalar/tf_scalar_dashboard/tf-scalar-dashboard.html

@@ -243,7 +243,7 @@ <h3>No scalar data was found.</h3>
 
         _tagFilter: {
           type: String,  // upward bound from paper-input
-          value: '.*',
+          value: '',
         },
         _categories: {
           type: Array,

Diff for: tensorboard/plugins/text/tf_text_dashboard/tf-text-dashboard.html

@@ -118,7 +118,7 @@ <h3>No text data was found.</h3>
 
         _tagFilter: {
           type: String,  // upward bound from paper-input
-          value: '.*',
+          value: '',
         },
         _categories: {
           type: Array,