Internationalization: Mark up more of Dashboard Variables and Browse/Search Dashboards (#63518)

* Extract dirty translations from main

* Translate some variable phrases

* Translate nav bar

* Translate search/browse

* Fix header returning null

* Translate search results type

* fix test

public/app/features/variables/adhoc/picker/AdHocFilter.test.tsx

@@ -29,7 +29,7 @@ describe('AdHocFilter', () => {
     await selectEvent.select(selectEl, 'key3', { container: document.body });
 
     // Select value
-    await userEvent.click(screen.getByText('select value'));
+    await userEvent.click(screen.getByText('Select value'));
     // There are already some filters rendered
     const selectEl2 = screen.getAllByTestId('AdHocFilterValue-value-wrapper')[2];
     await selectEvent.select(selectEl2, 'val3', { container: document.body });

public/app/features/variables/adhoc/picker/AdHocFilterBuilder.tsx

@@ -1,6 +1,7 @@
 import React, { FC, useCallback, useState } from 'react';
 
 import { DataSourceRef, SelectableValue } from '@grafana/data';
+import { t } from 'app/core/internationalization';
 import { AdHocVariableFilter } from 'app/features/variables/types';
 
 import { AdHocFilterKey, REMOVE_FILTER_KEY } from './AdHocFilterKey';
@@ -64,7 +65,7 @@ export const AdHocFilterBuilder: FC<Props> = ({ datasource, appendBefore, onComp
       <AdHocFilterRenderer
         datasource={datasource}
         filter={{ key, value: '', operator, condition: '' }}
-        placeHolder="select value"
+        placeHolder={t('variable.adhoc.placeholder', 'Select value')}
         onKeyChange={onKeyChanged}
         onOperatorChange={onOperatorChanged}
         onValueChange={onValueChanged}

public/app/features/variables/pickers/shared/VariableInput.tsx

@@ -43,7 +43,7 @@ export class VariableInput extends PureComponent<Props> {
         value={value ?? ''}
         onChange={this.onChange}
         onKeyDown={this.onKeyDown}
-        placeholder={t('variable.picker.input', 'Enter variable value')}
+        placeholder={t('variable.dropdown.placeholder', 'Enter variable value')}
       />
     );
   }

public/app/features/variables/textbox/TextBoxVariablePicker.tsx

@@ -1,6 +1,7 @@
 import React, { ChangeEvent, FocusEvent, KeyboardEvent, ReactElement, useCallback, useEffect, useState } from 'react';
 
 import { Input } from '@grafana/ui';
+import { t } from 'app/core/internationalization';
 import { useDispatch } from 'app/types';
 
 import { variableAdapters } from '../adapters';
@@ -70,7 +71,7 @@ export function TextBoxVariablePicker({ variable, onVariableChange, readOnly }:
       onBlur={onBlur}
       disabled={readOnly}
       onKeyDown={onKeyDown}
-      placeholder="Enter variable value"
+      placeholder={t('variable.textbox.placeholder', 'Enter variable value')}
       id={`var-${variable.id}`}
     />
   );